Chechen separatists have killed 11 Russian soldiers and wounded five others in a double ambush in the province, Interfax news agency has reported.
It quoted a source in the military command as saying the rebels attacked the troops after their vehicle hit a mine and ran off the road near the town of Urus-Martan.
An armoured troop carrier that went to their aid then ran into another mine and came under fire from the rebels.
"As a result 11 Interior ministry troops were killed, five were wounded and one is missing," the source said. The Interfax report could not be immediately confirmed with officials.
In 2000 Russian troops ended a short-lived independence for Chechnya won in the first war with Russia in 1994-96. But Chechen separatists have kept up a war against Russian forces.
Chechnya's pro-Moscow president, Akhmad Kadyrov, was killed on May 9th by a bomb at a stadium in the regional capital of Grozny.