PATNA: Suspected Maoist rebels killed seven policemen with a landmine blast in eastern India Tuesday, officials said, the second attack blamed on the insurgents in Bihar state in less than a week.

“Seven policemen died when armed Maoists targeted a security patrol with a landmine,” district police chief Upendra Kumar Sharma told AFP.

The blast occurred in the district of Aurangabad, 150 kilometres (93 miles) from the state capital Patna.

On Saturday suspected guerrillas opened fire on a passenger train in Bihar's Munger district, killing three railway security men.

Earlier last month the outlawed insurgents ambushed a security patrol and killed four troopers in the central Indian state of Chhattisgarh.

The Maoists have grown from a rag-tag band of ideologues into a potent insurgent force, creating a so-called “Red Corridor” that stretches throughout central and eastern India.

They demand land and jobs for the poor, and want to establish a communist society by toppling what they call India's “semi-colonial, semi-feudal” form of rule.