The EU's top counter-terrorism official on Wednesday condemned a wave of attacks on mosques, churches and religious schools in the Netherlands made following the murder of a Dutch filmmaker critical of Islam.
At least 15 Muslim buildings, including two schools, have been attacked in the two weeks since a suspected Islamic militant shot and stabbed Theo van Gogh.
"Everybody should be concerned at the spiral of revenge attacks and the cause of that, the murder of Mr van Gogh," Gijs de Vries told a news conference in Brussels.
"There is no excuse for such attacks."
A surge in violence in a country known for its tolerance prompted its prime minister, Jan Peter Balkenende, to urge better integration of immigrants. But he insisted this involved work from both sides, and meant respect for freedom of speech.
"Integration also means respecting and abiding by the fundamental rules of our society: freedom of speech, freedom of belief, respect for the democratic rule of law, which should offer individuals the protection to which they are entitled," he said in a speech to the European Parliament in Strasbourg.