Maoist rebels killed seven policemen and injured 10 others in an ambush in the dense forests of central India on Saturday, police said.

A squad of 61 policemen from a special task force formed to combat Maoists was on an exercise in the forests of Sukma district in Chhattisgarh state when the ambush occurred, the officer said.

Chhattisgarh is among the Indian states worst-affected by the Maoist insurgency, which has killed more than 6,600 civilians, militants and security personnel countrywide since 2005.