State Minister for Home Affairs Lutfozzaman Babar also wanted to know from the energy ministry why the local people grew so angry against Asia Energy's coal mine project that led to this "unfortunate incident."

"This is unfortunate. I've asked the DC, SP and TNO for administrative inquiry to ascertain what factors prompted the law enforcers to open firing on the angry people," Babar told reporters at his ministry.

On the killing of four policemen at a cattle market in Naogaon last Friday, the state minister instructed to strengthen police drive against the outlaws.

The inspector general of police was asked to monitor the pending cases against the underground extremists.

So far 60 police and ansar personnel were killed by members of the underground outfits since the country's independence.

"I've ordered the IGP to monitor the cases against the underground extremists through the monitoring cell at the Police Headquarters," he said.