French, German and Belgian police arrested more than two dozen suspects in anti-terrorism raids Friday, as European authorities rushed to thwart more attacks by people with links to Mideast Islamic extremists.br Rob Wainwright, head of the police agency Europol, told The Associated Press that foiling terror attacks has become "extremely difficult" because Europe's 2,500-5,000 radicalized Muslim extremists have little command structures and are increasingly sophisticated.