Witnesses said the police fired shotguns and teargas shells at the stranded Pakistanis who threw back brickbats and shoes on the law enforcers during the two-hour clashes in the morning.

The clash ensued as around 20,000 stranded Pakistanis attempted to march towards the Pakistan High Commission at Gulshan from the Geneva Camp at Mohammadpur, breaking police barricade, to submit a memorandum.

The memorandum demanded a tripartite meeting, involving the Stranded Pakistanis General Repatriation Committee (SPGRC), and the governments of Pakistan and Bangladesh, by March 23 to reach an agreement to settle their repatriation, ensure their safety and security and stop eviction of their camps in Bangladesh.

The police detained at least 15 people, including SPGRC leaders, during the incident. Six of them were later shown arrested while the rest were released.

SPGRC leaders said stranded Pakistanis from 34 camps in Dhaka started gathering at the Geneva Camp and adjacent area in the early morning to attend the "peaceful" march to the Pakistan High Commission.

As the procession started for the Pakistan High Commission at around 11:15am, the police barred it putting up barricades and asked the stranded Pakistanis over loud speakers to go back to their camps.

At one stage, the stranded Pakistanis broke the barricades and tried to advance, which prompted the police to charge baton on them. The stranded Pakistanis also started pelting brickbats, shoes and sandals at the police force.

The law enforcers fired shotguns and 56 teargas canisters to disperse the demonstrators, the police said.

Shop-owners shut down their shops while vehicular traffic remained halted during the chaos.

Police Sub-Inspector Mezbah Uddin filed a case accusing the arrested six and around 1,500 others of attacking the police and creating obstruction to their activities.

According to a 1992 census, there are 2,38,400 stranded Pakistanis in 66 camps in 13 districts in Bangladesh.