The forces have arrested 21 people, including a rebel area commander Pandu Majhi, from the camps, officials said.

In all, 28 companies of the police force of the two states as well CRPF personnel have been pressed into the operation, which began on March 8.

DGP Bhupinder Singh told The Indian Express confirmed four Maoist training camps had been destroyed but refused to give their exact locations. “The aim behind this operation is mainly to familiarise the forces with the terrain. We are also trying to win the confidence of the local people,” he added.

Maoist leader Kishenji on Thursday vowed revenge against the operation and asked the two states to stop it. “We will strike if this operation is not stopped,” he said in a statement.

In another development, the state government has furnished all the details on the Maoists activities in the state to the Centre that it had asked for. “They asked us to file a report on the number of arrests and other details and we have sent the report,” Home Secretary Ardhendu Sen said.

Meanwhile, a decision has been taken to allow the police of one state to enter the territory of another in pursuit of Maoists after any strike. This is one thing that West Bengal had been demanding as it always maintained that most of the Maoists are based in Jharkhand and after carrying out an operation in Bengal they run away to their base.