By Waliur Rahman BBC reporter in Dhaka

The Bangladeshi authorities say soldiers will continue their controversial anti-crime drive indefinitely.

Hasina led a walk out by opposition MPs

Home Minister Altaf Chowdhury told parliament troops would not head back to the barracks until law and order had improved.

Thousands of troops were deployed across the country a month ago to arrest criminal suspects and recover illegal firearms.

More than 20 people have died in army custody and the opposition Awami League says the army is being used to silence government opponents.

Prime Minister Khaleda Zia denies the accusation and says the army is acting neutrally.

Walk out

Speaking on the first day of parliament's winter session, Mr Chowdhury said the government had deployed the troops to halt the deteriorating law and order situation.

He said the people had welcomed the decision.

Army is neutral, says PM

The minister said Operation Clean Heart would continue unless and until law and order had improved.

Opposition leader Sheikh Hasina said that the troop deployment reflected the government's failure to maintain law and order.

She also wanted to know why three members of parliament, including two Awami League MPs, had been arrested without charge.

When Speaker Jamiruddin Sircar rejected her proposal to begin a debate on the subject, all the MPs from her party walked out of the chamber in protest.

False accusations

Army authorities laid down a set of criteria for complaining against suspected criminals on Thursday, asking people not to make false allegations or complaints out of personal rivalry.

The advice followed a wave of allegations that false information had led to harassment of innocent people and human rights violations by soldiers.

The naval commander in a south-eastern district was recently withdrawn after reports that his troops had beaten up the local police chief and a physician on the basis of allegations received.

A week ago, a 75-year-old man died in hospital following his arrest by soldiers on the basis of complaints which turned out to have been related to a land feud.

Soldiers have arrested more than 5,000 people since being deployed.