Police have put in place an exceptional security cover around the Assembly ahead of the budget session from February 20, the day chief minister Jitan Ram Manjhi would have to prove his majority in the House.

For the first time, senior police officers have been drafted for round-the-clock surveillance in the protected zone. Shibli Numani, the Sachivalaya deputy superintendent of police, said on Sunday: 'We have put in multi-layer security arrangements and deployed officers not below the rank of station house officer to keep a watch on the highly protected zone, particularly the Assembly, in view of the recent political developments.' The Assembly premises falls under the jurisdiction of Sachivalaya police station.

He added that while security of some VIPs has been enhanced in the wake of threat to their lives, special arrangements are being made for the budget session this time. 'Security has been provided to VIPs, irrespective of their party affiliation and faction,' Numani said.

Sources in the headquarters said night vigil has been intensified in the prohibited zone, which houses the official residences of chief minister, ministers, former ministers and legislators.

The station house officers of different police stations apart from those under whose jurisdiction the area comes have been assigned to carry out night patrolling in shifts.

'Additional forces have been deputed at the bungalows of some influential MLAs, who hogged the limelight after making controversial statements and indulged in mud-slinging against political opponents. Even FIRs have been lodged by some MLAs, who apprehended threat to their lives,' a senior police officer said.

Former minister Bima Bharti had lodged a complaint with the Secretariat police station last week against art, culture and youth affairs minister Vinay Bihari, accusing him of pressuring her to side with chief minister Jitan Ram Manjhi.

JDU MLA Anant Singh submitted another complaint at the same police station against the chief minister, accusing him of instigating people by issuing controversial statements.

Visitors are being frisked strictly at the Secretariat gates. No outsider was allowed to enter the premises without valid identity proof or passes issued by the authority. Quick response teams have been kept ready at the Secretariat police station. 'Women cops have also been assigned the task,' the police officer said, adding that CCTV cameras would also keep an eye on suspected troublemakers.

Sources said Patna senior superintendent of police Jitender Rana took stock of the security measures in the wake of a directive issued by the acting secretary of the Bihar Vidhan Sabha a few days ago.

Intelligence agencies have sounded an alert in the wake of political uncertainty.

A senior officer of the intelligence wing said: 'In the past, Maoists used to issue threat letters to blow up the Assembly building. But, this time in the wake of political crisis, the police and watch and ward employees of the Assembly will have a tough time.'

Rana said adequate security arrangements have been made for the budget session and the law makers.