People are dying from extreme heat, which is also killing a large number of chickens and destroying tea plants
Police have detained a man over the assault at Ishwarganj Upazila late Monday.
Superintendent of Police Syed Nurul Islam said that the attack was reported from a village of the Sarisha Union.
Unidentified men hacked Mostafizur Rahman around 8:45pm outside the mosque while he was leaving after conducting prayers, he said.
"Locals managed to nab one of the attackers, who has been identified as Abdul Ahad and handed him to police. We have launched an investigation," said senior officer Islam.