The man was first spotted on the building at 9:15 p.m. GMT on Saturday. The London Fire Brigade, London Ambulance Service and Metropolitan Police force were joined at the scene by specialist negotiators.
The 23-year-old man dressed in a grey long sleeved top and dark trousers was eventually arrested on 5 a.m. GMT on Sunday on suspicion of criminal damage and trespassing on the roof. He remained on the roof all night and was observed pacing around between the buttresses of the historic monument where UK law is decided.
It is not currently known why the man was on the roof or how he got there. A Scotland Yard spokeswoman said “At 9.15pm officers were made aware of a man trespassing on the roof at the Palace of Westminster. London Fire Brigade and London Ambulance Service are in attendance. Officers are still trying to establish why he was on the roof. He appeared to be alone. Investigations are ongoing.”
It is not known whether the man was protesting for a cause. No banner was displayed from the building but the site has been used to stage protests before. Five thousand protesters had gathered outside Parliament earlier on Saturday for a climate change demonstration but it is currently unknown if the man is linked to this event.
The roof of Parliament was used by a protest group campaigning against the proposals for a third runway at Heathrow Airport in 2008. Greenpeace activists slid ladders through railings around the building a year later to use the roof to protest about climate change, unfurling yellow banners from the building.
Eyewitnesses reported that the man appeared to be “moving around” the building but did not seem to be protesting or campaigning. Before his arrest on Sunday morning, occasional muffled shouts were heard from the roof in response to attempts at conversation from police officers.