Some of the worst Shia-Sunni sectarian strife has occurred before (under Saddam regime responsible for at least 400,000 Shia deaths) after the American invasion of Iraq, steadily building up to present. According to one estimate, as of early 2008, 1,121 Sunni suicide bombers have blown themselves up in Shia-majority Iraq. Sunni suicide bombers have targeted not only thousands of civilians, but mosques, shrines, wedding and funeral processions, markets, hospitals, offices, and streets.