Dhaka, Dec. 27 -- Four people, including two children, have been injured after an explosion at a madrasa in South Keraniganj on the outskirts of Dhaka.

The blast took place on Friday afternoon at the Ummal Qura International Madrasa in the Hasnabad area.

Explosives and bomb-making materials were recovered from the building following the blast, according to police.

Local residents say the madrasa has around 50 students, but classes were not being held on Friday because it was the weekly holiday.

A journalist in South Keraniganj, citing local accounts, said the explosion caused the walls of two rooms used by the madrasa to collapse, with cracks appearing in the roof and supporting columns. The owner of a neighbouring building also repor...