Law enforcement agencies have already been ordered to step up security at the diplomatic zone and other key points in the capital.

"We simply can't dismiss the possibility of subversive acts. We always take such apprehensions seriously," State Minister for Home Affairs Lutfozzaman Babar told reporters after a meeting on law and order yesterday.

Asked whether they have any specific intelligence reports in this regard, he avoided a direct reply and said, "We're working on it."

But sources said the participants at the meeting discussed in detail the probabilities of blast incidents, and a rapid increase in organised crimes and murders during the Ramadan and Puja and asked the law enforcers to keep maximum vigilance.

The minister alerted high officials of the police, Rapid Action Battalion (Rab), Ansar and Coastguard that the top-listed criminals holed up abroad might return to the country shortly and set off a flurry of criminal activities.

Eight hundred members of police and Rab will patrol the capital to manage traffics and check crimes, especially mugging, during and in the run-up to the religious ceremonies of the Muslims and Hindus.

Split in 200 squads, they will work in two shifts to zero in on the troublemakers. Each squad will be assigned a particular area of the city.

Besides, the Armed Police Battalion (APBn) men will make patrols on 18 motorbikes.

Already 16 motorbike squads are working in the diplomatic zone and the number will be increased at the beginning of the Ramadan.

Babar directed the law enforcers to mark out spots where mugging incidents are frequent and undertake pre-emptive drives.

He also ordered for frequent raids at slums, hotels and guesthouses to round up the troublemakers.

Over 33 mobile courts will work from September 20 to check food adulteration and other crimes in the capital.

The same day, control rooms will start functioning at district and upazila levels to receive people's complaints about law and order.

Besides, there will be arrangements at the home ministry, police and Rab headquarters to receive complaints from across the country.

The state minister asked the law enforcers to stop extortion on the highway saying that if unchecked it might lead to shooting up of prices of the essentials during the Ramadan.

The meeting endorsed a ban on fireworks and use of crackers during Shab-e-barat.

Asked whether four people arrested in connection with the grenade attack on British High Commissioner Anwar Choudhury might as well have a role in the assassination of former finance minister Shah AMS Kibria, Babar said, "We haven't got any such information yet. We'll need at least 3/4 days to be clear about it."

"Although the arrestees have confessed to having role in the attack on British high commissioner, we need a few more days to have their versions corroborated and know details of the incident," he added.