Smoke billows out of a disused building in Old Street, central London, after a fire broke out this morning
Fire has ripped through an old Royal Mail building in central London on Thursday morning.
Six fire engines and 35 firefighters initially tackled the blaze in the block in Old Street after it broke out before 9am.
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That number has since increased to eight fire engines and 60 firefighters.
Police are also at the scene.
The blaze left a giant plume of smoke billowing out over the area known as London's Tech City.
London Fire Brigade said on Twitter it received 20 999 calls to "very visible fire". It had no reports of injuries, the brigade added.
The cause of the fire is not currently known, but it appears to have broken out of a building site.
It comes just a day after the fire brigade saved historic pub Ye Olde Cheshire Cheese, following a fire in a nearby flat.