A huge blast at a gas plant in south-eastern Nigeria has left an unknown number of people dead and injured.

A truck is reported to have exploded as it was off-loading butane cooking gas in the town of Nnewi in Anambra State. Locals are said have been there gathering gas for meals on Christmas.

Reports of fatalities vary from low numbers to more than 100, including factory workers.

A fire raged for more than five hours after the blast, witnesses said.

The dead and injured were taken to the Nnamdi Azikiwe University Teaching Hospital in Nnewi, which has a predominantly Christian community.

Staff inside the plant are reported to have been trapped.

"The fire burned beyond recognition all the workers who were inside that depot at that time and also all the customers inside that depot," Chukwuemerie Uduchukwu, who went to the scene, told the BBC.

'Huge inferno'

The ferocity of the blast also damaged houses in the surrounding area.

Police spokesman Ali Okechukwu said there had been a "huge inferno".

Reports of the scale of fatalities vary. Mr Okechukwutold AFP news agency at least two people had died, while a reporter for Associated Press said they counted the remains of 100 bodies.

A witness told the Vanguard newspaper that the blast was triggered when a truck began discharging cooking gas without waiting for the mandatory cooling time.

Passers-by were also caught up in the explosion, the newspaper reported.

Witnesses described a huge fire with acrid black smoke hanging over the scene of the disaster.