Russian media outlets reported yesterday that the Russian Federal Security Service (FSB) has detained one of the suspected masterminds of the terrorist attack in the St. Petersburg subway on April 3.

The FSB Public Relations Center informed TASS that "the Russian Federal Security Service detained one of the masterminds of the St, Petersburg subway bombing in the Odintsovo district of the Moscow oblast today (April 17).

He was reportedly identified as a 27-year-old Abror Azimov, “originally from Central Asia.”

According to the FSB statement, Abror Azimov trained suicide bomber, Akbarzhon Jalilov. 

FSB officers have seized a service pistol from the suspected mastermind of a terrorist attack on the St. Petersburg metro as he was apprehended, as shows a FSB footage received by TASS on Monday.

Judging by the video, the suspect was detained near a railway station in Moscow oblast’s Odintsovo district west of Moscow.

One of the officers asked the man whether he realized what was going on.  “Yes,” he answered.  Then a combat pistol was removed from a rear trouser pocket, and two smartphones were also seized from the suspect.

The suspect has been taken for questioning to the Investigative Committee, which probes serious crimes, the FSB said.

Recall, an explosion on a train carriage in St Petersburg's subway killed at least 14 people and injured dozens more.

The blast hit a train travelling between two stations in the western city's center during mid-afternoon.

Another explosive device was later found at a nearby station but it was made safe by authorities.

The suspected suicide bomber has been named as 22-year-old Akbarzhon Jalilov, who is thought to have been a Russian national born in Kyrgyzstan.

Jalilov is suspected of triggering a homemade explosive device while on a train in a subway tunnel.

There was no immediate claim of responsibility for the attack, but Russia's Anti-Terrorism Committee said it was looking for the “perpetrators and organizers of the terror attack.”

FSB chief Alexander Bortnikov said in comments carried by Russian news agencies that six members of terrorist cells were detained in St Petersburg and two in Moscow.

FSB chief Bortnikov, who is also the head of the Russian National Anti-Terrorism Committee (NAC) as said at a NAC meeting on April 11 that the suspects are members of a clandestine terrorist cell.  “Large amounts of weapons and means of destruction have been seized. Search is underway for the masterminds and the possible accomplices,” he said.