New Delhi  - Eleven policemen were killed in a landmine blast triggered by Maoist rebels in India's eastern Jharkhand state Wednesday, news reports said.

The incident took place the village of Serengda-Aruanga in Jharkhand's West Singhbhum district, about 130 kilometres south of the state capital Ranchi, PTI news agency reported.

A team of the Central Reserve Police Force (CRPF) and state police was returning from a two-day patrol of Saranda forest where Maoist rebels are believed to have bases, when their vehicle was blown up by the landmine, Jharkhand police chief VD Ram was quoted as saying.

Ram said the victims included a CRPF officer. Six policemen were injured.

Additional police and paramilitary forces have been rushed to the village, PTI reported.

Maoist rebels, who say they are fighting for the rights of the landless and tribal people, operate in 13 Indian states and usually target police personnel and government installations.

According to independent estimates, more than 600 people, including civilians, security personnel and rebels, were killed in Maoist violence in 2008.

Recently, Maoist violence has been largely concentrated in four states, Bihar, Chhattisgarh, Orissa and Jharkhand, India's Home Minister P Chidambaram told Parliament in February.

At least 80 per cent of the 1,591 incidents of Maoist violence in 2008 took place in these four states, he said.

Prime Minister Manmohan Singh has described the Maoist insurgency as one of the gravest internal security threats facing India.(dpa)