ROSTOV-ON-DON, Russia – A small group of suspected Islamic militants were barricaded inside an apartment house in southern Russia Saturday in a standoff with hundreds of security forces who evacuated neighboring buildings and cut off gas supplies.

The suspects were holed up inside a second floor apartment in Nalchik, the capital of the Kabardino-Balkariya region, in the latest in a series of confrontations between law enforcement authorities and extremists in the volatile North Caucasus region, which includes Chechnya.

Last month, security forces killed seven alleged Islamic extremists in the same city in a two-day battle with members of the Yarmuk group, a radical Islamic group affiliated with Chechen warlord Shamil Basayev. The Interior Ministry said the alleged militants in Saturday’s standoff also were members of Yarmuk.

At least three suspects were inside the apartment, according to a duty officer at the southern district office of the Interior Ministry. Earlier, a spokesman for the Nalchik police department, who did not give his name, told Ekho Moskvy radio that 20 militants were inside the five-story building. The discrepancy could not immediately be explained.

Two armored personnel carriers and more than 300 gun-toting riot police were at the scene, and security forces evacuated residents from surrounding buildings and cut off natural gas flows in the neighborhood.

The Interior Ministry officer said the suspects were believed to be lightly armed and discussions aimed at their surrender were under way. Russia’s NTV television reported, however, that the suspects were refusing to negotiate and the situation had remained unchanged for hours.

In a separate operation in Nalchik, some 870 miles south of Moscow, three people were detained in a private house and police confiscated one gun, four grenades and Islamic literature produced by the conservative Wahhabi sect, according to the Interior Ministry duty officer. The detainees, including two women, were seized without any violence, the officer said. One woman was a Chechen and the other two suspects were from Karachaevo-Cherkessiya, another troubled region in southern Russia.

The Yarmuk group was blamed in a December 2004 attack on an office belonging to the Federal Drug Control in Nalchik, when raiders killed four of the agency’s employees, looted its arsenal and set the office ablaze.

Russia’s southern provinces have been plagued by a spillover of violence from Chechnya, including the September school hostage-taking in the city of Beslan in which some 330 people were killed.