London Fire Brigade has said that twelve engines and 60 firefighters are on the scene.
News 24 reports:
“There are reports of cylinders involved in the fire. We believe the roof area was under refurbishment,” an LFB spokesperson said.
CNN has reported that propane tanks were on the roof but were moved because of explosion fears.
There have been no reports of injuries. The fire department is said to be in the process of controlling the flames.
Police have blocked access at Chancery Lane at the junction with Fleet Street. No traffic is allowed in the area at present.
A Tribunals Service spokeswoman said: “We are at present trying to contact those who were due to have hearings in the building tomorrow to advise them not to attend and we will be in touch with them about arranging new dates.”