At least 150 people have been killed in an explosion at a petrol station in the Ghanaian capital of Accra, according to Sky News.

President John Dramani Mahama said the country would observe three days of mourning for the victims.

The government will also allocate about million of dollars for relief operations and to repair damaged infrastructure, he added.

The blast was caused by flooding that swept stored fuel into a nearby fire, according to an official.

Some reports said the accident in the Kwame Nkrumah Circle area may have spread from a nearby home or lorry terminal.

Michael Plange, who lives nearby, said many of those killed had taken shelter under a shed at the station because of two days of torrential rain that has left many parts of the city submerged and people stranded.

Emergency workers, soldiers and police were seen recovering bodies from the scene.

Graphic footage on national television showed the dead being piled onto the back of a truck, with charred bodies trapped in the wreckage.