Bangladesh has been hit by a series of bombs recently

The protests were organised by the country's leading Muslim clerics, who have denounced the attacks as against the tenets of Islam.

It comes a day after a suicide bomb attack killed at least six people in northern Bangladesh.

At least 25 people have been killed in a series of bombings across Bangladesh this year.

The main demonstration took place at the Baitul Mukarram national mosque in Dhaka after Friday prayers.

It is a duty for all Muslims to stand up against those who are killing in the name of Islam Cleric Obaidul Haq

"Islam prohibits suicide bombings. These bombers are enemies of Islam," the chief cleric, Obaidul Haq, told worshippers.

"It is a duty for all Muslims to stand up against those who are killing people in the name of Islam," he said.

He also urged clerics in the hundreds of thousands of mosques across Bangladesh to mobilise public opinion against the bombers.

Similar protests took place in towns and cities around Bangladesh.

Suspects questioned

The government, which has urged the clerics to organise demonstrations after Friday prayers, says the organisations behind the recent bombings are abusing Islam and damaging its reputation.

"These bombers are enemies of Islam and must be stopped," an official at the ministry of religious affairs was quoted saying by Reuters news agency.

Many people were badly hurt in the bombings

The police have questioned some suspects in connection with Thursday's blast in the northern town of Netrakona, according to reports.

"Those who have carried out the attack have thrown a challenge for us. But we shall capture them," junior interior minister Lutfozzaman Babar told reporters.

Militant group

Police at the scene of the attack said two men rode up on a bicycle and dropped a package on the street.

One bomber died, the other was injured, police said.

Last month, a powerful bomb exploded inside a library near a courthouse in Gazipur, leaving seven people dead and about 50 others injured - police described it as the country's first ever suicide bombing.

In a second attack on the same day, two policemen were killed in a bomb attack outside a courthouse in the port city of Chittagong.

Two days later one person died in another bomb attack in Gazipur.

The government blamed a banned militant group, Jamaat-ul-Mujahideen, for the explosions and a series of earlier attacks.

More than 400 people have been arrested but the BBC's Roland Buerk in Dhaka says it is thought the masterminds remain at large.

The Jamaat-ul-Mujahideen wants to establish Islamic law in Bangladesh.