An improvised explosive device packed with projectiles was set off at a St. Petersburg supermarket late Wednesday, injuring 13 people. The suspect was reportedly caught on security camera footage as he left a backpack that detonated later at the coat check.

President Vladimir Putin has instructed security forces to kill all terrorists who threaten the lives of security officers after calling Wednesday's explosion in St. Petersburg a "terrorist attack."

"You know that a terrorist act was committed in St. Petersburg yesterday," Putin said Thursday at a ceremony awarding hundreds of Russian troops who served in Syria.

The Russian head of state said he instructed the FSB chief to act “decisively” against returning terrorist fighters who threaten the lives of security officials.

"Don't take any prisoners, liquidate the bandits on the spot," Putin told the 600 servicemen and women who gathered at the Kremlin.

Earlier this month, security forces arrested seven suspected members of an Islamic State (IS) sleeper cell in St. Petersburg who were reportedly preparing a suicide bombing at the city’s Kazansky Cathedral. IS is a terrorist organization banned in Russia.

Putin's spokesperson Dmitry Peskov clarified the president's statements to journalists later on Thursday.



"The phrase was in reference to those who harbor plans to commit terrorist acts in our country," he was cited as saying by the state-run RIA Novosti news agency.