Cape Town — An explosion has set the Engen oil refinery in Durban South aflame, IOL reports.

Emergency services reported to the scene where fire and smoke were seen by residents. "I first thought it was a tremor, when I heard the windows rattle, but saw smoke billowing in the sky," one said after hearing the explosion during the night. The blast was heard in many parts of Durban. Refinery workers who spoke to TimesLIVE under condition of anonymity said the explosion occurred in the northern complex of the refinery. "I'm pretty sure it's the reactor. This plant is old," one employee said.

Garrith Jamieson, an Advanced Life Support Paramedic, said a tanker explosion may have been the cause of the fire and that roads around the refinery have been closed off while emergency teams attend to the fire.

Robert McKenzie, KwaZulu-Natal emergency spokesperson, said that six people were treated for smoke inhalation, The Sowetan reports.

He said a block of flats on Beach Road caught fire though no injuries were reported after the blaze was extinguished.

According to Engen spokesperson Gavin Smith, the fire was extinguished at 08h45, adding: "Engen's emergency response team and eThekwini emergency services were immediately mobilised to contain the incident. The cause of the fire is currently under investigation."