A suicide bomber struck in an area between major shrines in the Iraqi Shiite holy city of Karbala on Sunday, causing casualties, an official from one of the shrines said. Jamal al-Din Shahristani, an official at the Imam Hussein shrine, said an engineer working on a project between the site and the Imam Abbas shrine blew himself up, causing an unspecified number of casualties. The shrines for the two grandsons of the Prophet Mohammed are among the holiest sites in Shiite Islam, and are visited by hundreds of thousands of pilgrims each year.