TAMBOV, April 4. /TASS/. The perpetrators and instigators of the St. Petersburg terrorist attack will be found, although the actual attacker seems to have died in the blast, Russian Prime Minister Dmitry Medvedev said.

"There can be no doubt that our law enforcement agencies and secret services will do everything possible to find all those involved in this [the St. Petersburg metro blast] and punish them," the prime minister said while meeting with staff members of an enterprise in the Tambov region.

"Despite the fact that the actual attacker seems to have died in the blast, as he must have been a suicide bomber, but that such crimes are never plotted by a single person," Medvedev pointed out.

According to him, "there is always a large number of various accomplices, monsters who brainwash people and make them carry out terrorist attacks."

"We are actually on the frontline of the fight against international terrorism and it has been hard for our country but we should carry the fight through, otherwise the number of terrorist attacks will increase instead of decreasing," the Russian prime minister said.