A suicide car bomber struck a busy Baghdad commercial district Monday, killing at least 21 people, setting cars on fire and damaging a nearby Sunni shrine, police and hospital officials said, according to The Associated Press. The blast went off at 2 p.m. (1200 GMT) in the Sinak market area on the east side of the Tigris River, just as U.S. and Iranian diplomats were wrapping up a historic meeting aimed at ending the violence wracking the country. Insurgents carried out several mortar and car bombing attacks throughout the capital Monday and even waged a lengthy gunbattle with police in broad daylight. The wave of violence, which killed 36 people across Baghdad, came despite a nearly 15-week-old U.S.-led security crackdown in the city. Another 33 bullet-riddled bodies were found handcuffed, blindfolded and showing signs of torture in different parts of Baghdad, the apparent victims of ongoing sectarian violence. The deadliest attack Monday was the car bombing in the Sinak district, near the Abdul-Qadir al-Gailani mosque.