Lalgarh, March 25: Security forces engaged Maoists in a series of encounters spanning over 12 hours today in the forests of West Midnapore, within 30km of Lalgarh town, the offensive dubbed the “biggest” against the rebels in Bengal.

CRPF sources said the joint forces fired nearly 2,500 rounds and used 12 mortar shells during the encounter that began around 7am.

District superintendent of police Manoj Verma said: “This is the biggest offensive against the Maoists in Bengal so far. The encounter continued for about 12 hours.” A police officer said sporadic exchange of fire continued till late tonight.

A.K. Singh, 25, a commando of the CRPF’s special unit, COBRA, took a bullet hit on his right shoulder and was taken to hospital.

“We planned the offensive after receiving information that Maoist action squads had taken shelter in the area (encircled by Lalgarh, Pirakata, Dherua and Chandra, all Maoist hotbeds) and that a top Maoist leader… someone like Kishan, might be with them,” director-general of police Bhupinder Singh said.

Singh said a number of people had been arrested and the security forces had recovered three improvised explosive devices. Police sources said three Maoists were arrested.

“The encounters took place in the area where the Maoists had hidden former officer-in-charge of Sankrail police station Atindranath Dutta after kidnapping him,” the DG added.

A CRPF officer claimed that at least five Maoists could have been killed or injured in the encounter. However, no bodies had been recovered till late tonight.

A police officer said mobilisation of forces had began from 3am today.

“Nearly 1,200 CRPF, state police and COBRA personnel, divided in groups, went on foot towards the jungles of Bhulagera, Lakshmanpur, Purnapani, Hatilot and Ranja,” the officer said.

Around 5am, the Maoists triggered an explosion near the Bhulagera forest, prompting the security forces to move towards the area.

“We realised that the Maoists had triggered the blast as a warning. We stopped and fired a few rounds of mortar shells towards the jungle. After about an hour, we started moving in the direction of the jungle again,” a police officer said.

The gun battle began after the Maoists fired at the forces from behind trees in the Bhulagera forest around 7am. By 9am, encounters had begun in Lakshmanpur, Purnapani, Hatilot and Ranja forests.

“At all these places, the security forces first fired a few rounds of mortar shells in the direction of the forests, forcing the Maoists to retreat. The forces then entered the forests and took position behind trees and mounds of earth,” another officer said.

A senior cop said the security forces were trying to corner the Maoists towards Pirakata. “We are trying to cut off their retreat by mobilising additional forces at Pirakata,” the officer said.