Local interior ministry troops were driving on the main Caucasus highway in two light vehicles on Friday when several explosive devices were detonated by remote control, Tass news agency quoted officials as saying.

The Chechen interior ministry in Grozny, however, denied the report, saying the incident was a road accident in which five people were killed including one policeman.

President Vladimir Putin has vowed to destroy Chechnya's separatist rebels, but attacks on Russian troops and local pro-Moscow forces continue daily.

Russian troops have fought rebels for about a decade in Chechnya. The war has killed thousands of Russian soldiers and tens of thousands of Chechens.