Maoist rebels have killed at least 17 police officers and injured 20 more in a raid on a police camp in north-eastern India. Two rebels were also killed.

Dozens of rebels on motorbikes stormed the camp in West Bengal state firing guns and throwing grenades. It was the deadliest Maoist attack since October last year, when 17 police officers were shot dead in the west of the country.

The Maoist insurgency began as a peasant uprising in 1967. Since then it has spread to 20 of the 29 Indian states, in what the rebels claim is a fight for the country’s poor and tribal populations. Thousand of people have died since the uprising began.