MAKHACHKALA: Russian police say 13 insurgents have been killed in the country's volatile Caucasus region, including four in an operation commanded by Chechnya's president, himself a former militant.

A spokesman for the Interior Ministry in the republic, Magomed Deniev, said four militants were killed Thursday in the capital Grozny in the operation commanded by Ramzan Kadyrov.

He said seven others were killed in an operation in Chechnya's mountainous south, where insurgents shelter in the rugged territory.

It was an unusually high one-day death toll for Chechnya, where separatists have been less active than neighbouring Dagestan.

Dagestan interior ministry spokesman Vyacheslav Gananov said two insurgents were killed by police during the night in the Dagestani capital Makhachkala after opening fire on police who stopped their car.