Investigators working out what caused fireball near Elephant and Castle station

Tap above to watch video report by Martin Stew

Investigators are working out what caused an explosion and fireball near Elephant and Castle railway station on Monday which sent black smoke billowing over south London.

London Fire Brigade said 600 people were evacuated from surrounding properties while others were told to keep windows closed.

Footage posted on Snapchat moments after the fire had begun showed a police officer carrying two children out of a restaurant complex in Elephant Road, just yards away from where the outbreak began.

A video of the fire posted on social media showed a small explosion resulting in a fireball.

Video from Twitter/@MeganJearum

London Ambulance Service confirmed six people ended up being treated at the scene, with one being taken to hospital.

James Ryan, station commander for Shoreditch, said firefighters were called to the railway arches under Elephant and Castle train station, where the fire was inside a car garage and spread to several cars and a telephone box.

It later ignited further, spreading to three other commercial units and the railway station and nearby buildings were evacuated.

A spokeswoman for the Metropolitan Police said: “Our officers were involved in a number of activities to keep the public safe and away from the area as well as supporting with evacuations. I believe this picture [of the officer carrying the children] was taken as officers were evacuating the local area where the fire broke out.”