LONDON — Amnesty International workers in London walked off the job Tuesday for the second strike in as many months in an embarrassing setback for an organization that campaigns for the rights of workers and is considered one of the world's pre-eminent human rights advocates. The walkouts are a public airing of staff complaints that have been building for years, with tensions rising dramatically in recent weeks as Amnesty's international operations prepare to re-organize. The changes include transferring some of its 500 jobs from a centralized London base to 10 regional hubs around the world — part of an effort to be closer to the hotspots where human rights violations occur. The organization says it's not really sure how many jobs will go, and that uncertainty has caused frustration and anger among its employees. The group's current crisis is raising questions about its ability to remain a leading human rights advocate in a world no longer defined by Cold War era divisions. Last week, Amnesty's program director for the Americas, Susan Lee, resigned, expressing shock at “senior management's failure to honor its commitments to treat staff fairly and with respect.” — AP