Four suspected members of an illegal armed group were killed Wednesday in an operation in St. Petersburg, Russia's second largest city, by the Federal Security Service, Tass news agency reported. 
The operation was conducted in an apartment block in St. Petersburg to detain persons who had been put on a federal wanted list and were suspected of taking part in illegal armed groups in the North Caucasus. 
"During the detention the above mentioned persons offered resistance and attempted to kill law enforcers by opening gunfire. Four persons in an apartment were killed by return fire," a security spokesman told Tass, adding that no civilians or law enforcers were hurt in the exchange.

Source: QNA