Fifteen fire engines carrying 70 firefighters have rushed to Somerset House as thick plumes of black smoke soar into London's sky.

Emergency services arrived at Somerset House after a blaze was reported at 11.59am.

The cause of the fire is not yet known but London Fire Brigade received 20 calls reporting the fire.

London Fire Brigade also confirmed a 32-metre ladder was being used at the scene, with crews from Soho, Dowgate and Islington among those tackling the blaze.

Ten fire engines rush to Somerset House as thick black smoke seen for miles over LondonTWITTER

"Fifteen fire engines and around 100 firefighters have been deployed to a fire at Somerset House.

"Crews are tackling flames located in part of the buildings roof.

"Two of the Brigade's 32m ladders have been sent to the scene to support firefighting operations.

"Traffic in the surrounding area will be impacted as crews respond.

"The Brigade's Control Officers have taken over 20 calls reporting the fire, with the first received at 1159.

"Crews from Soho, Dowgate, Islington and surrounding fire stations are attending the scene. The cause of the fire is not yet known

A social media user added: "Slightly disturbed by the amount of smoke currently pouring out of the roof of Somerset House."

Another said: "Looks like there’s a fire at Somerset House, I’m really hoping that’s not the Courthauld Gallery going up. Watch this space."

Somerset House, which welcomes three million visitors every year, was scheduled to host a breakdancing event between 2pm and 8.30pm today.

Choreographer Jade Hackett was due to assemble dancers for the London Battle event at Somerset House's iconic open-air courtyard.

Somerset House said: "Returning for a second triumphant year, London Battle takes over Somerset House’s iconic open-air courtyard with a day of dance and breaking showcases, workshops, live DJs and a big outdoor party, all culminating in a head-to-head dance battle between the four corners of London."