Massive explosion heard at a refinery in South Africa's Durban

A massive explosion, which was heard about 25 kilometres away, rocked an Engen refinery in South Africa's Durban at 7 a.m. (GMT 0500) on Friday, according to Xinhua News Agency.

It is not clear what caused the explosion, or if any casualties occurred.

According to Engen's website, the Durban refinery has a crude refining capacity of 120,000 barrels per day. It is the second-largest crude refinery in South Africa.

(With input from Reuters)