Gas explosion kills seven and blows walls off building on busy street in Bangladeshi city of Chittagong

Twenty five injured in early morning blast

Firefighters join the rescue operation (Reuters)

At least seven people were killed and another 25 injured after a gas pipeline exploded in southeastern Bangladesh on Sunday, police said.

The explosion in the Patharghata area of Chittagong collapsed portions of a boundary wall of a nearby building, local police chief Mohammed Mohsin said.

He said at least 25 people were hospitalised and firefighters joined the rescue operation.

It was not immediately clear what caused the explosion.

News reports said the road in front of the explosion site was busy with people and tricycle rickshaws. A boundary wall fell on the people on the road.

The explosion took place when residents were preparing for the day's work in the morning, Mr Mohsin said.

Chittagong is 134 miles southeast of the capital, Dhaka.

Associated Press