Police say at least eight policemen have been killed in a land mine blast suspected to have been carried out by Maoist rebels in their stronghold in eastern India.

Senior police officer K.B. Singh says another five policemen were injured in the attack late Wednesday in Koraput region, nearly 550 kilometers (345 miles) south of Bhubaneshwar, the capital of Orissa state.

The injured have been hospitalized, Singh said Thursday.

The insurgents, who say they are inspired by Chinese revolutionary leader Mao Zedong, have been fighting for more than three decades, staging hit-and-run attacks against authorities as they demand a greater share of wealth from the area's natural resources and more jobs for farmers and the poor.

The government says the rebels are India's biggest internal security threat.