Baghdad, Jan 4, SPA -- Iraqi security forces launched a major search operation in Baghdad on Wednesday for the sister of the interior minister, kidnapped on Tuesday. Police closed two bridges over the River Tigris linking the city centre to the militarized Green Zone, which houses government buildings and the U.S. embassy. Witnesses said some parts of the city were closed to cars while traffic in other areas was much heavier than usual as police set-up impromptu checkpoints. "The main reason for the security measures is the kidnapping of the minister's sister yesterday," Deputy Interior Minister Ahmad al-Khafaji told Reuters. "We're conducting search operations. We need to take serious precautions in Baghdad these days." Gunmen abducted the woman, a sister of minister Bayan Jabor, in a heavily policed area of the capital. A police source said assailants drew up alongside her convoy and opened fire, killing a driver and a bodyguard. They seized the woman, who has not been named, and escaped. --SPA 13 30 Local Time 10 30 GMT www.spa.gov.sa/316776