A scotland yard spokeswoman said.
Westminster palace roof.
By then the flames had also spread close to the wooden roof of westminster hall.
London fire brigade and london ambulance service are in.
But fixing the palace of westminster might change british politics for good.
An incendiary bomb struck the chamber of the house of commons and set it on fire while another set the roof of westminster hall alight.
The palace of westminster site was strategically important during the middle ages as it was located on the banks of the river thames known in medieval times as thorney island the site may have been first used for a royal residence by cnut the great during his reign from 1016 to 1035.
Once up they unfurled a 15 metre 50 ft banner protesting against the british government s plans to update the trident nuclear programme.
The roof westminster hall was probably originally supported by pillars giving three aisles but during the reign of king richard ii this was replaced by a hammerbeam roof by the royal carpenter hugh herland the greatest creation of medieval timber architecture which allowed the original three aisles to be replaced with a single huge open space with a dais at the end.
The rest is gothic revival.
As politicians dither over repairs the risk of fire flood or a deluge of sewage only increases.
Measuring 20 7 by 73 2 metres 68 by 240 feet the roof was commissioned in 1393 by richard ii and is a masterpiece of design.
St edward the confessor the penultimate saxon monarch of england built a royal palace on thorney island.
The worst raid took place on the night of 10 may 1941 when the palace took at least 12 hits and three people were killed.
When the fire engines arrived the house of lords was already destroyed and the commons was ablaze.
Westminster hall and its hammerbeam roof in the early 19th century.
The prime minister lord melbourne quickly directed efforts to douse the roof with water which saved the hall although much of the rest of the palace was lost.
In march 2007 another four members of greenpeace made their way to the palace s roof by means of a nearby crane which was being used for repairs to westminster bridge.
The work was largely undertaken by the king s chief mason.
Purcell is overseeing the ten year rolling programme of repairs to all cast iron roofs at the palace.
The cast iron tiled roofs were installed on wrought iron structures in the mid 1800s and used innovative technology.
At 9 15pm officers were made aware of a man trespassing on the roof at the palace of westminster.
