TEHRAN — Iran's opposition leader Mehdi Karroubi was surrounded while in the house of a senior cleric in the holy city of Qom on Sunday by regime supporters who also attacked his car, an opposition website said. Karroubi had travelled to Qom in central Iran for a mourning ceremony and later called on Ayatollah Yousef Sanaei at his home when "forces linked to the power (regime) surrounded the house," Kaleme.com said.