Hilton Park Lane evacuated after hotel fire: UPDATED

Firefighters are tackling a blaze at the Hilton Hotel Park Lane, London, forcing the evacuation of guests and staff, including Black Eyed Peas singer Will.I.Am.

The London Fire Brigade (LFB) was called to the five-star Mayfair hotel just after 1845 BST, according to the BBC.

Sports journalist Sam Cunningham (@samcunningham), who was among those forced to flee the building, has been live tweeting as events unfolded.

He said at around 2030 BST: "I'm hearing it was caused by a generator on this lower roof. Contained. Could be hours before people let back in."

Around 1,500 people were evacuated from the building while at least four pumps and 20 firefighters tackled the blaze.

The cause of the fire is unknown at this stage and there have been no reported casualties.

A number of Twitter users have posted photos, including Cunningham (above left) and Lucy O'Dwyer (@LucyODwyer - photo below, taken from a Windows 7 phone):

UPDATE: 2230 BST: Fred Sirieix (@fredsirieix1), general manager of Galvin at Windows - the Michelin-starred restaurant and bar on the 28th floor of the London hotel, said on Twitter: "All ok here on Park Lane. Thank you."

A few minutes later, the London Fire Brigade (@LondonFire), announced on Twitter: "We believe the fire at the Park Lane Hilton is now out but are still checking the hotel's ducting just to make sure."