Power was wiped out in 135,000 buildings across Havering and Essex when a fire spread to electrical cables.

Romford, Gidea Park, Hornchurch, Harold Hill, Upminster and Rainham were all hit at about 4.20pm, as well some areas of Essex including Brentwood, Ockendon and the Intu Lakeside shopping centre in Thurrock.

Fire crews were called to Hacton Lane, Upminster at 3.40pm on Tuesday after two 30-metre cables running along the bridge over the River Ingrebourne were badly damaged by a grass fire.

It is thought to have started when school leavers burned their books and the fire spread.

Georgia Edwards, 18, of Bevan Way, said she was taking her brother to the park when a group of schoolchildren ran towards them.

“They told me to turn around,” she said. “Fire engines were there and out of nowhere a fire started. Kids were running away and told us they saw kids setting fire to their school books.

“Apparently they were burning planners and stuff. We all just watched.”

The power outage lasted almost 30 minutes, causing chaos as buildings were evacuated, traffic lights stopped working and water supplies were cut off.

There was another 15-minute interruption just after 5pm before power was fully restored but thick black smoke could be seen in the sky until the blaze was put out at 7pm.

UK Power Networks confirmed to the Recorder that 135,000 buildings had been hit.

James Whitelock photographed the fire and the aftermath from his home in Clement Way.

He said: “Everyone was out on the street to see what was going on.”

People took to social media to vent their frustration at the lack of electricity.

Two estate blocks in Rainham were without water for most of the night and business owners complained of trade losses.