(Updates after police begin removing protesters)
By Toby Sterling and Bart H. Meijer
AMSTERDAM, Oct 7 (Reuters) - Police began forcibly removing climate change activists who blocked a major street in downtown Amsterdam on Monday, arresting 50 after they defied orders to move their demonstration onto a nearby square.
Traffic around the city centre was disrupted as about 900 protesters from the group Extinction Rebellion gathered on Stadhouderskade, in front of the Netherlands' national museum, to demand more action to tackle climate change.
The Amsterdam protests are part of an international campaign by the group to raise public awareness about climate change. Police in London said on Monday they had so far arrested 21 climate activists, while dozens of protesters blocked traffic at a main square in Berlin.
Starting before dawn, the protesters in Amsterdam held pamphlets saying "SORRY that we blocked the road, but this is an emergency".
"The climate crisis is not being taken seriously enough by politics, and also not by the companies. That's why I joined," said one protester, who gave his name as Christiaan.
Protesters linked arms to form a barricade at either end of the block, and set up tents in the centre of the street. Organisers said they intended to stay for weeks.
But riot police sealed off nearby streets by mid-morning, forcing some protesters onto the square behind the museum. Later police began carrying away, one by one, demonstrators who had remained on the street.
The protesters sang songs and chanted slogans including "rebellion!" and "the oceans / are rising / and so are we".
They carried a large banner reading "TELL THE TRUTH about the climate and ecological crisis that threatens our existence".
City authorities had granted the group a licence to demonstrate on the condition that it not block traffic.
The national museum, or Rijksmuseum in Dutch, was at first inaccessible due to the protesters and a police barricade, but police later set up gates and allowed tourists to enter.
A second group of protesters gradually formed on the square behind the museum, saying that those who remained on the street were determined to stay until they were arrested.
(Reporting by Toby Sterling and Bart Meijer; Writing by Anthony Deutsch; Editing by Gareth Jones)
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