Riot police in Bahrain fired tear gas and stun grenades Thursday to disperse thousands of opposition supporters gathered near the square that was the epicenter of the nation's Shiite-led demonstrations earlier this year, an activist said. The violence is a setback to efforts by the tiny island's Sunni rulers trying to open reconciliation talks with the Shiite opposition in the Gulf kingdom. Activist Nabeel Rajab said the protesters at Manama's Pearl Square chanted: "Down, down Hamad" – a...