An unidentified gunman opened fire in the receiving office of the local branch of Russia’s Federal Security Service (FSB) in the Far Eastern city of Khabarovsk on Friday, the FSB Public Relations Center told TASS.

"At 17:02 local time (06:02 GMT), an unidentified man entered the FSB receiving office and opened fire before crossing the control zone," the Center said.

A FSB officer and a visitor, a CIS member state citizen, died in the shooting, while another visitor suffered wounds. The gunman was killed.

"The attacker was killed. Investigation activities are underway," the FSB sources said.