On April 3, 2017, the day the terrorist attack was carried out, Akbarjon Jalilov (named by the investigation as the perpetrator) entered the metro at the "Akademicheskaya" station with a backpack and a bag containing explosive devices.

One and a half minutes before entering the station, Jalilov entered the vestibule from the passenger exit side and observed the metro control service employees through a glass barrier. One was in the duty booth watching the turnstiles, another, instead of monitoring the metal detector frames, was talking to the duty officer, and the third inspector was absent due to illness (replaced by two trainees). At the same time, a police officer was absent from the station: he was called to the neighboring "Grazhdansky Prospekt" station to assist in processing a detainee with a small amount of drugs. Later, the prosecutor's office found out that the metal detectors’ sound was turned off. Jalilov passed unnoticed from the vestibule entrance to the escalator.

Half an hour before the explosion, around 14:01, surveillance cameras installed in the metro recorded Jalilov in the passage to the "Ploshchad Alexandra Nevskogo-2" station. He was wearing a red-orange down jacket with a fur hood, a blue hat on his head, and a backpack on his back. Jalilov no longer had any other items in his hands. He was captured by cameras again around 14:03 on the way from the escalators to the "Ploshchad Alexandra Nevskogo-1" station.

At 14:21, a message appeared in the largest city group on VKontakte dedicated to traffic accidents and emergencies about an unattended item found at the "Ploshchad Vosstaniya" station. Around 14:28, this station and the passage to "Mayakovskaya" were closed for entry and exit. Eyewitnesses described law enforcement officers approaching the bag with a device for detecting explosives. The author of the published photo confirmed to the press that it was taken around 14:01.

On the right, a pedestrian crossing is visible, which hid half of the train from the driver, preventing him from immediately understanding what had happened.

Around 14:33 local time, an explosion occurred in a train car on the section between the "Sennaya Ploshchad" and "Tekhnologichesky Institut" metro stations. According to eyewitnesses, the explosion happened just after the train departed from "Sennaya Ploshchad." The train was operated by driver Alexander Kaverin, whose cabin fire alarm system signaled a fire in the 4th car at that moment. Following instructions, the driver ensured the train was moving without significant speed reduction and continued to the next station. Seconds later, many messages began coming through the internal "passenger-driver" communication, but they overlapped and were unintelligible. The train reached the next station, "Tekhnologichesky Institut," which also had a driver turnover point. Due to severe damage from the shockwave, the doors on the exploded car jammed and were manually opened by passengers, after which evacuation began. Since a passage in the middle of the platform partially hid the second half of the train, driver Kaverin could not immediately grasp the situation; instead, he first called the instructor driver Osipov from the turnover point, then reported by radio to the dispatcher about a false fire alarm on this train. However, after hearing from people on the platform about the explosion, the driver contacted the dispatcher again and reported the terrorist attack and that there were "injured and dead" on the train.

"At that time, there were quite a lot of people in the car: everyone was sitting, many standing. The explosion thundered between the 'Sennaya' and 'Tekhnologichesky Institut' stations. There was a deafening bang, then a sharp smell, smoke. We immediately moved to the end of the car, a crush formed. Two women immediately felt unwell and fainted. Everything happened while the train was moving; it did not stop. At 'Tekhnologichesky Institut,' everyone got off. We saw that the adjacent car was wrecked, windows broken, no light, blood. People were being pulled out from there, some carried, some supported. There were many victims, definitely about 10–15 people." — one eyewitness.

According to Interfax agency, the explosive device’s power was about 200–300 grams in TNT equivalent. "Ploshchad Vosstaniya" station. On the right, a granite wall where one of the IEDs was found (left — passage to "Mayakovskaya" station).

The homemade explosive device found at "Ploshchad Vosstaniya" was equipped with shrapnel elements. It was defused by bomb disposal experts. This device had remote control, and mobile communication was temporarily jammed during defusing. The power of this explosive device was 1 kilogram in TNT equivalent; the device was disguised as a fire extinguisher.

A decision was made to close the metro stations "Nevsky Prospekt," "Mayakovskaya," and "Ploshchad Vosstaniya." Later, the stations "Park Pobedy," "Elektrosila," "Moskovskie Vorota," "Frunzenskaya," "Tekhnologichesky Institut," "Sennaya Ploshchad," and "Gostiny Dvor" were closed; at 15:40, all other stations were closed. Bus routes along metro lines were organized by GUP "Passazhiravtotrans," JSC "Third Park," and LLC "City Sightseeing Moscow." The city government instructed all public transport to carry passengers free of charge. Several taxi operators made similar decisions. Travel on the Western High-Speed Diameter was made free on the evening of April 3. After the terrorist attack, a transport collapse occurred in St. Petersburg.

Governor of St. Petersburg Georgy Poltavchenko ordered the activation of the emergency response plan. Due to the terrorist attack, security measures were also strengthened in the Moscow and Nizhny Novgorod metros, as well as in all Russian airports and railway stations. Additionally, vigilance was increased in the Minsk and Almaty metros.

At 20:44, the St. Petersburg metro management announced partial restoration of metro operations: the sections "Vladimirskaya" — "Baltiyskaya" and "Gorkovskaya" — "Park Pobedy" remained closed. Around 22:00, movement on the Kirovsko-Vyborgskaya line was fully restored. From the morning of April 4, the St. Petersburg metro resumed full operation on all lines and stations, but some stations were temporarily closed due to threat reports that were later unconfirmed.

According to Health Minister Veronika Skvortsova on the morning of April 4, the death toll was 14 people: 11 (including the terrorist) died on the spot, 1 during transportation, and 2 immediately upon arrival at the hospital. A list of thirteen victims, excluding the terrorist, was published by the Investigative Committee of Russia on April 5. On April 12 and 21, the deaths of two more victims became known. Thus, the total number of fatalities rose to 16.

Prime Minister Dmitry Medvedev instructed Skvortsova to organize assistance for the victims. In total, 89 people sought medical help. According to the Russian Ministry of Emergency Situations, 51 wounded were hospitalized; surgeries began as early as 15:50 on April 3; two wounded could not be saved despite treatment. As of May 3, one month after the attack, 12 people remained hospitalized in the city; the discharge of the last victims was reported on August 3. GUP "St. Petersburg Metro" promised to compensate the victims for damages sustained during the explosion. The Investigative Committee of the Russian Federation (IC RF) opened a criminal case under Article 205 of the Criminal Code of the Russian Federation (terrorist act). The case was taken up by the Main Directorate for Investigating Especially Important Cases of the IC RF. Operational support for the investigation is provided by the FSB of Russia. Initially, according to the President of Russia, domestic and criminal versions of the explosions were considered alongside the terrorist act version. But by 16:30 on April 3, the Prosecutor General's Office of Russia officially declared the metro explosion a terrorist act.

Media reported that surveillance cameras in the St. Petersburg metro allegedly recorded the suspected terrorist. Later, the person named as a suspect, retired Airborne Forces Captain Andrey (Ilyas) Nikitin, appeared at the police and declared his innocence. After verification, he was released.

Preliminary data indicated that the explosion was carried out by a suicide bomber, whose fragmented remains were found in the car. On April 4, the IC RF confirmed that the suicide bomber was Akbarjon Jalilov, born April 1, 1995, in the Kyrgyz city of Osh, who obtained Russian citizenship in 2011. According to the IC RF, his genetic traces were also found on the bag with explosives at "Ploshchad Vosstaniya." Gazeta.ru, citing a law enforcement source, writes that although Jalilov was born in Kyrgyzstan, he may have been ethnically Uzbek (the city of Osh is a place of compact Uzbek residence). Since 2011, he worked in St. Petersburg at a car repair shop; there are also reports that he worked as a cook. He was interested in Islam and had religious acquaintances. A Gazeta.ru source reports that Jalilov adhered to the ideas of one of the extremist organizations. A friend of Jalilov described him at work as a reserved person and told REN TV journalists that Jalilov wanted to participate in cutting off the hand of a thief who stole money from colleagues.

Turkish media reported that Jalilov was deported from Turkey in December 2016 due to overstaying, having been in the country for about a year. The FSB suspects that he trained in ISIS militant camps in Syria.

According to Kommersant, security services knew about the preparation of the terrorist attack in St. Petersburg from a Russian detained after returning from Syria who cooperated with the Islamic State. Phone numbers of accomplices were known and were blocked after the attack. On June 26, the FSB announced that the suicide bomber, his accomplices, and handlers used the Telegram messenger at all stages of organizing and preparing the terrorist act.

On April 5, eight alleged accomplices of the terrorists were detained in St. Petersburg. According to the investigation, since November 2015, the suspects recruited Central Asian natives in the city to participate in terrorist organizations "Jabhat al-Nusra" and "Islamic State." It is reported that the IS recruitment network was known but its exposure was planned in a few days.

A search was conducted in the apartment on Grazhdansky Prospekt rented by Jalilov, during which bomb-making components were found.

On April 6, six more people were detained in St. Petersburg, and two in Moscow. Their names: Seyfulla Khakimov, Ibragibzhon Yermatov, Dilmurod Muidinov, Bakhram Yergashev, Azamjon Makhmudov, Mahamadyusuf Mirzaalimov, Shokhista Karimova, and Sodik Ortikov. All are from Central Asia. They were identified by studying Akbarjon Jalilov’s phone calls and email correspondence. Investigators named them involved in the terrorist attack. Having come from Tajikistan, Kyrgyzstan, and Uzbekistan, they worked in a sushi bar and, in particular, in the "Lesnoye" cafe, where Jalilov himself cooked.

Firearms, ammunition, and an explosive device similar to the one found at "Ploshchad Vosstaniya" were found among Jalilov’s alleged accomplices. During a special operation to detain suspects in a rented apartment on Tovarishchesky Prospekt in St. Petersburg, the bomb had to be defused on site. For this, police and special services evacuated residents of the apartment building.

In court, it was revealed that shortly before the explosion, Akbarjon Jalilov called an unidentified person, who in turn contacted Sodik Ortikov.

On April 7, the investigation announced a version that two people were supposed to detonate bombs in the St. Petersburg metro. It is assumed that Jalilov was to bring two bombs into the metro, activated by pressing buttons. One was intended for himself, and the other for an accomplice with whom they planned a double terrorist attack. However, the second potential suicide bomber did not come to the meeting for some reason. Then Jalilov, having disposed of the extra bomb at "Ploshchad Vosstaniya," boarded the train with one bomb in his backpack and carried out the suicide bombing. Since a third bomb was found in the detainees’ apartment, the investigation assumes it was also planned to be detonated in the city in places of mass gatherings.

The Nevsky District Court of St. Petersburg arrested six suspects in the explosion case for two months. Only Ibragibzhon Yermatov among the arrested admitted acquaintance with Akbarjon Jalilov.

The prosecutor's office also sent materials to the IC RF to decide on initiating a criminal case under the article "Negligence": the supervisory authority found that the sound on metal detectors was turned off at all metro stations.

On April 17, the FSB of Russia detained one of the alleged organizers of the terrorist attack — 27-year-old native of Central Asia Abror Azimov in the Odintsovo district of the Moscow region. Special services believe he was preparing the suicide bomber. The next day, it became known that Abror Azimov fully admitted guilt but later retracted his testimony.

On April 20, the head of the FSB of Russia, Alexander Bortnikov, stated that the customer of the terrorist attack had been identified, without naming him. On the same day, the Basmanny Court of Moscow arrested Akram Azimov — Abror Azimov’s brother. According to the investigation, he received money for preparing the terrorist attack in Turkey from an active participant of an international terrorist organization and then transferred it to the perpetrator of the attack in St. Petersburg.

On April 27, it became known that the State Committee for National Security (GKNB) of Kyrgyzstan is checking Sirozhiddin Mukhtarov (also known as Abu Salah al-Uzbek) for involvement in the St. Petersburg metro terrorist attack.

On May 11, the FSB of Russia detained the 11th suspect in the terrorist attack case, Kyrgyz citizen Mukhamadyusuf Yermatov. Yermatov is suspected of terrorism and illegal arms trafficking. On May 12, he was arrested by the Basmanny Court of Moscow.

On the anniversary of the attack, April 3, 2018, the Investigative Committee stated that all those involved had been identified: from customers and organizers to perpetrators. A total of 11 people belonging to a radical Islamist community were arrested.

According to investigators, all suspects did not know each other and communicated using "modern means of communication." The participants of the criminal group were identified through "thorough analysis of electronic traces."

On August 23, 2018, the investigation requested the pre-trial detention in absentia of Kyrgyz native Sirozhiddin Mukhtarov — then considered the main customer of the terrorist attack.

On December 10, 2019, the 2nd Western District Military Court, at an off-site session in the building of the 1st Western District Military Court, delivered a guilty verdict in the terrorist attack case. Abror Azimov was found guilty of organizing and financing the terrorist attack and sentenced to life imprisonment; 10 of his accomplices were sentenced to terms from 19 to 28 years (Akram Azimov and Mukhamadyusuf Yermatov received 28 years of strict regime colony each, Ibragimzhon Yermatov — 27 years of strict regime colony, Sodik Ortikov — 22 years of strict regime colony, Dilmurod Muidinov, Azamjon Makhmudov, Mahamadyusuf Mirzaalimov — 20 years of strict regime colony, Seyfulla Khakimov and Bakhram Yergashev — 19 years of strict regime colony). The only female defendant, Shokhista Karimova, was sentenced to 20 years in a general regime colony. The convicted and their lawyers intend to appeal the verdict.

On July 25, 2019, the investigation established the whereabouts of the main customer and ideological inspirer of the terrorists, Sirozhiddin Mukhtarov. At the court hearing in the terrorist attack case, prosecutor Nadezhda Tikhonova stated that he was in the Syrian city of Idlib.

On September 10, 2022, the Russian Ministry of Defense reported the liquidation of Sirozhiddin Mukhtarov.

According to the British newspaper The Independent, supporters of the Islamic State on the Internet welcomed the explosions (which occurred after a wave of ISIS propaganda calling for strikes on Moscow), although ISIS itself did not claim responsibility at that time.

On April 25, 2017, information appeared that responsibility for the terrorist attack was claimed by a previously unknown group allegedly linked to "Al-Qaeda."

On April 3, 2020, on the 3rd anniversary of the terrorist attack, a memorial plaque with the names of the deceased was installed at the "Tekhnologichesky Institut" station. After the attack, St. Petersburg metro stations began to close more frequently due to unattended items found. According to Fontanka’s calculations, this happened 640 times in 2017 alone, with about 7,000 items found in total. Additional inspections were conducted on 27 million passengers. Experiments with total inspections were conducted at some stations, but these measures led to collapse and were abandoned.

Sources:

https://ru.wikipedia.org/wiki/Теракт_в_Петербургском_метрополитене_(2017)