Ranchi, Jan 17 (Agencies): Three Maoist guerrillas,involved in killing more than three dozen security personnel, escaped from a jail in West Singhbhum district of Jharkhand early on Monday,

"Three hardcore Maoists Dhirendra,Sandeep and Nirbhay escaped from jail by breaking the ceiling of their cell.

They were in jail for the last two to three years," an official of Chaibasa jail told.

All three were the members of zonal committee of the outlawed Communist Party of India-Maoist (CPI-Maoist).

Sandeep and Dhirenra were allegedly involved in two incidents of ambush in Saranda jungle in 2002 and 2003 where more than 40 security personnel were killed.

The police say their escape was a big blow to the state's anti-Maoist operations.

"It is indeed a great setback for the police," Jharkhand Police's spokesperson R.K. Mallik told agencies.

Police fear that the Maoists were regrouping in the Saranda jungle.

An intensive combing operation has been launched in the state to arrest the escaped Maoist prisoners.