PYATIGORSK, February 9 (RIA Novosti) - A special forces officer and two gunmen were killed in a police operation Thursday to oust a militant group that barricaded itself in two residential buildings in the Stavropol Territory in southern Russia, a local police source said Thursday.

The fighting started at about 2p.m. (11a.m. GMT).

Five gunmen remain in the buildings, according to Yevgenia Androsova, press secretary of the Federal Security Service's branch in the Stavropol Territory, which borders on the war-torn republic of Chechnya.

She said the militants were holding two residential buildings on the opposite side of the street.

Armored vehicles have been sent to the scene, but they decided not to shell the buildings for fear that civilians might still be in the buildings.

According to Russian TV channel NTV, the militant group was uncovered during a police operation to check passports.