BOSTON (AP) — Boston police have arrested more than 50 protesters from the Occupy Boston movement after they ignored warnings to move from a site near their official encampment.Police spokesman Jamie Kenneally said the arrests began about 1:30 a.m. Tuesday and were mostly for trespassing.The protesters, part of the national Occupy Wall Street effort, had moved from Dewey Square to a second site across the street, along the Rose Kennedy Greenway. A local conservancy group recently planted $150,000 worth of shrubs along the greenway and officials said they were concerned about possible damage.Boston police had warned protesters that they would have to return to Dewey Square and had issue leaflets saying they could not occupy the greenway.Protesters who were arrested were taken to a police station in Government Center.