A 23-year-old man whom police have not identified was arrested early Sunday in London after spending the night wandering around on the roof of the British parliament building.

The man was on the top of the Palace of Westminster, where both houses of Britain's parliament meet, for about eight hours, reports said. He was carrying no signs or banners and appeared to have no political agenda.

The U.K.'s Sunday Express reports:

"Video footage of the man ... seen as he walks around the roof in a grey top and dark trousers, appeared online yesterday."Police negotiators, fire brigade and London ambulance services rushed to the scene at 9:15 pm last night."

An eyewitness told The Daily Telegraph: "He's just walking up and down, looking a bit vacant."

He was reportedly not taken into custody until 5 a.m. London time. It was not clear why it took authorities so long to remove him from the government building.

The Telegraph says the man is being held on "suspicion of criminal damage and trespassing" and adds that "the roof has been the scene of campaign stunts by groups in the past."

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