DHAKA ? At least four people were injured in the Bangladeshi capital Dhaka on Thursday when a bomb exploded in a crowded commercial area, police said.

Local police chief Rezaul Karim told AFP that the injured were taken to hospital with minor wounds.

"One of the injured is a ruling party official from the southern Bagerhat district," Karim said, adding that it was not known who was behind the attack.

The blast comes three weeks after another explosion in Dhaka in which 15 people were injured. It targeted an influential ruling party legislator who is a relative of Prime Minister Sheikh Hasina.

The lawmaker, Fazle Noor Tapash, was not hurt in last month's blast.