By Moazzem Hossain BBC reporter in Dhaka

Two men picked up by Bangladesh army soldiers during a massive anti-crime drive have died in Dhaka while being interrogated.

Family members of the victims complained the two men were tortured to death by members of the Bangladesh army during the government's massive anti-crime drive which started on Thursday.

A Bangladeshi army source confirmed Yakub Ali and Jahangir Hossain, both supporters the ruling Bangladesh Nationalist Party (BNP), had died while being held by the security force.

Members of the ruling party are among those arrested

But the source declined to give details of how they died.

This is the first allegation of torture against the Bangladesh army since 40,000 of its troops were deployed to towns and cities across Bangladesh to take part in a massive security operation targeting criminals.

Connected

Nearly 1,300 people were arrested on the first day of the massive security operation, including some local level politicians accused of having links to criminal groups.

Most of those alleged criminals and politicians arrested on Thursday are connected to the ruling Bangladesh National Party.

The government sought the army's help to crack down on crime in the wake of a steady worsening of law and order.

Supporters of the ruling party staged demonstrations against the arrests in different parts of the country, and one man was killed when soldiers opened fire on one of these protests in the northern town of Bogra.

Supporters of the main opposition Awami League party also held demonstrations protesting against the arrest of their leaders.

But a senior opposition leader Abdul Hamid said the Awami League did not object to the use of the army to fight crime.

He warned, however, that the drive against crime would not yield positive results if the army was used to persecute the opposition.

Massive operation

Nearly 40,000 troops are taking part in this campaign.

Every night smaller groups of army troops are conducting raids at possible criminal hideouts.

During these raids, mobile telephone networks are shut down so that criminals can not pass any information between themselves.

The army has not been used to deal with crime since the early 1970s

Army check posts have been set up at key points in big cities and on highways, and vehicles are being stopped and searched for illegal arms at these check posts.

This is the first time the army has been used to deal with criminals under a democratically-elected government since the early 1970s.

Prime Minister Khaleda Zia was under pressure from international donors and the business community to take immediate and effective steps to improve the situation.

The government says the operation has been largely successful so far and that the army will stay on the streets until the law and order situation returns to normal.