The deceased included Bachchu Mia (70) from Kishoreganj and Belal Hossain (60) from Dakkhinkhan, Dhaka.
Sources said the two groups-supporters of Maulana Zubair and Maulana Saad Kandhalvi-locked horns with each other in a fierce rivalry for supremacy over the venue in Tongi, Gazipur.
The deadly clash ensued at 3:00 am when a faction attempted to take control of the site, which is used for a big congregation of world Muslims every year.
Later in the day, home adviser Lt Gen (retd) Jahangir Alam Chowdhury expressed his government's firm resolve to bring those involved in the killings to trial.
"There is no scope to spare those involved in the murders. The perpetrators will be brought to justice," he told the media after holding separate meetings with both sides at his ministry amid escalating tensions.
Meanwhile, Bangladesh Khelafat Majlish secretary general Maulana Mamunul Haque claimed the death count to be four. "The deaths were due to a violent attack by Saad supporters."
Asked if Saad supporters would be allowed to participate in the upcoming ijtema, the adviser said, "If the two factions can settle their issues through discussions, Saad supporters will be permitted to join the congregation."
When asked, he said the government has not cancelled the ijtema date yet.
The followers of Maulana Zubair demanded a ban on the organisational activities by the supporters of Maulana Saad, also calling for the government not to allow them to join the congregation.
Maulana Mamunul made the demand after a meeting with seven advisers to the interim government at the secretariat.
"They (Saad followers) are friends of an anti-Bangladesh force. Resisting this evil force is not only the responsibility of Alem-Olama, but also the duty of the state and administration, too."
"We've demanded that the followers of Maulana Saad be banned designating the faction as a terrorist outfit," added Maulana Mamunul.
He said a case would be filed over the gory incident.
Asked if the government allows Saad followers to hold ijtema, this religious leader replied, "We hope the government will not do this mistake."
Meanwhile, Saad supporters vacated the ijtema ground on the bank of the Turag river after a government directive.
In another development, Dhaka police banned all forms of rallies, processions, demonstrations and gatherings at Kamarpur, Abdullahpur, Uttara Sector 10 and their adjacent areas along the riverbanks following the clash.
The restriction took effect from 2:00 pm on Wednesday and would remain in place until further notice, according to a public notification issued by the Dhaka Metropolitan Police (DMP).
DMP commissioner SM Sazzat Ali said the ban has been enforced under section 29 of the DMP Ordinance to maintain order in light of the prevailing situation.
The violence prompted the deployment of additional security forces, including four platoons of the Border Guard Bangladesh, to quell the situation.
Police and Rapid Action Battalion also beefed up security in Kakrail Mosque and Dhaka Medical College Hospital areas.
talhabinhabib@yahoo.com