Police say suspected Maoist rebels have detonated a land mine and killed seven policemen and injured six others in eastern India.

The policemen were returning from a search operation in Palamau district of Jharkhand state when the land mine blew up their vehicle late Wednesday.

A top Jharkhand police officer, S. N. Pradhan, said Thursday that four policemen died instantly while three others died in a local hospital.

The rebels have been fighting for more than three decades in central and eastern India to demand a greater share of the region's natural resources for its indigenous peoples.

The rebels say they are inspired by Chinese revolutionary leader Mao Zedong. The Indian government says the rebels are the country's most serious internal security threat.