A deadly blast that rocked the Nigerian city of Ibadan overnight was caused by explosives stored by illegal miners, the Oyo state governor has said.

Two people were killed and 77 others injured in the explosion that has affected seven suburbs of Nigeria's third most-populous city.

Crowds have thronged the site of the blast as rescue efforts continue.

A man whose mother's home was destroyed says she was in bed at the time of the blast and is now in hospital.

"The roof and everything went down. She was inside in her bed when it happened. She was rushed to the hospital naked and I'm going there now," he told the BBC as he was rushing to see her.

Buildings have been reduced to near rubble at the site of the blast and vehicles destroyed. Further away from the blast zone, windows have been blown out of houses and rooftops damaged.

Eyewitnesses say the explosion happened at around 19:45 local time (18:45 GMT) in Bodija, a residential district of district of the city.

It was heard across the city of Ibadan, the capital of south-western Oyo state.

One of the onlookers at the scene is a painter who had been working at one of the buildings that collapsed. He turned up to work in the morning and is unable to find his boss.

"I have been calling him but the number is not connecting and I saw that his vehicle has been destroyed," he told the BBC.

Oyo Governor Seyi Makinde posted a statement on Facebook promising that those responsible would be "brought to book".

"I have directed that the medical bills of all victims be covered by the government," he said.

"We will also be providing temporary accommodation for those whose houses were affected and ensuring that they are supported to rebuild their lives."