Ranchi, June 30 (IANS) At least three policemen were killed and four injured Monday when Maoist guerrillas exploded a land mine in a jungle in Jharkhand, the police said. Pramod Kumar Singh, a deputy superintendent of police, was patrolling with some colleagues when the mine went off near Pundiduri village, around 70 km from Ranchi. Singh was among the dead.

The authorities blamed the Communist Party of India-Maoist for the attack. The injured men were referred to the Rajendra Institute of Medical Science.

Maoists are active in 18 of the 24 districts in the state. In the last seven years, more than 1,200 people have been killed in violence linked to Maoists. These include 714 civilians and 320 security personnel.