Hundreds of anti-war demonstrators were arrested on Saturday at NATO headquarters as many of the protesters tried to enter the compound, organizers of the protest said.
The protest took place on the fifth anniversary of the Iraq War. The protest, under a campaign called "NATO GAME OVER," was held 10days before a NATO summit in Bucharest, capital of Romania.
The organization behind this campaign, Vredesactie, said about 500 people have been arrested. There was no confirmation from the police.
Vredesactie said more than 50 activists successfully got inside NATO headquarters despite a heavy police presence.
Police used water cannons to prevent protesters from gaining access to the compound in a suburb of Brussels.
The organization accused NATO of helping the wars in Iraq and Afghanistan. "Without NATO the war in Iraq and Afghanistan would not be possible," said Vredesactie in a statement.
NATO has made European countries logistic hubs for the U.S. military. European soldiers are also fighting in Afghanistan, it said.
On the NATO summit, it said Europeans do not want to use war and military threats to solve conflicts, as their leaders do.
"Missile defense, nuclear weapons, new military bases, soldiers to Afghanistan, ... the people do not want it. But governments do not listen to these wishes," the statement said.