Police in central India say Maoists rebels have killed five security personnel in two separate attacks in the central state of Chhattisgarh.

In one incident, at least three policemen were killed when their vehicle hit a landmine in Dantewada district Sunday.

Elsewhere, police say two paramilitary soldiers were killed when Maoists rebels ambushed them in the state's Kanker district.

At least one rebel was killed in retaliatory fighting.

Indian leaders call the 40-year Maoist insurgency the country's biggest internal security threat.

The rebels have infiltrated more than 20 Indian states, saying they are fighting for jobs and land for the poor.

Indian officials say close to 1,200 people were killed in rebel-related violence in 2010. More than 250 people have been killed so far this year.