MAKHACHKALA - Russian troops have reclaimed all villages in the southern region of Dagestan from Islamic militants and were combing the area Friday for scattered rebel fighters, an official said.

Refugees have started coming back to their homes in western Dagestan's Novolaksky region, after it was cleared of rebel groups who had invaded from neighboring breakaway Chechnya on Sept. 5, army commander Gen. Gennady Groshev said.

The main Russian forces have been moved to positions nearer to the border with Chechnya, to repel possible new offensives by Islamic

militants. Up to 1,500 rebels have congregated on the other side of the frontier, north of the latest fighting, Groshev said.

Police and Defense Ministry troops were also combing Dagestan for remaining rebels. Thirty-one suspected rebels and their collaborators have been detained, officials said.

Islamic militants twice crossed the Chechen border and seized villages in Dagestan since the beginning of August, clashing with Russian forces.

Russian police and Defense Ministry forces lost about 250 troops in the fighting since early August, officials said.

Col. Gen. Valery Manilov, deputy chief of the Army General Staff, claimed that Russian forces had killed more than 2,000 militants. But rebels have said that the Russian claims are exaggerated.

Russian jets were also bombing rebel bases in Chechnya to preempt new incursions. Moscow denied Chechen claims that the jets were hitting villages in the breakaway republic -- although some villages may have been hit inadvertently.

"Strikes have been delivered and will be delivered" against rebel bases in Chechnya, Interior Minister Vladimir Rushailo said Friday.

"But there have been no and will be no strikes against residential locations in Chechnya," Rushailo was quoted as saying by the Interfax news agency.