German police arrest suspected militants as Berlin gears up for Obama visit

By Thomas EscrittBERLIN (Reuters) - Police arrested four suspected Islamists in dawn raids in Berlin on Wednesday as the German capital geared up for a long weekend of mass gatherings, capped by a joint appearance by Chancellor Angela Merkel and former U.S. president Barack Obama.None were linked to the Manchester bomb attack which killed 22 people on Monday."We'll take another look, but our security plans are designed so we're well prepared for events like that in Manchester," Berlin's interior