A group of militants hurled homemade bombs at a group of police officers guarding Eid prayers in Bangladesh, killing at least two people and injuring several others, officials said.

At least one of the bombs exploded at a prayer congregation where hundreds of thousands of people had gathered in the district of Kishoreganj, about 90 kilometres north of the capital of Dhaka, for the Muslim holiday of Eidul Fitr, marking the end of Ramazan.

Police and local media said the explosion occurred at a school outside the prayer ground where at least 200,000 people were gathered. There were also exchanges of gunfire at the scene.

The country's information minister said the target of the attack was a police convoy patrolling the Eid prayer gathering. The blast killed one police officer and one other person, Minister Hasanul Haq Inu said.

“Up to nine police constables have been injured in the attack,” Inu told Indian broadcaster CNN-News 18.

Tofazzal Hosain, who is the district's deputy police chief, told AFP that several people had taken part in the attack and some had been armed with machetes — a hallmark of recent killings in Bangladesh.

“They first threw a small bomb targeting police and then attacked them with machetes. Police retaliated by returning gunfire,” he said.

The private Somoy TV station broadcast footage of a gunfight between police and a group of attackers and reported that the slain policeman had been hacked to death.

Azimuddin Biswas, the district administrator, told AFP that the attack had taken place on the premises of a nearby school and not on the actual prayer ground.