BAGHDAD - A parked car bomb struck a bus packed with workers in a volatile city south of Baghdad on Thursday, killing at least four people and wounding 24, police said.

Residents stand at the site of a bomb blast in Tuz Khurmato near Kirkuk, about 250 km (150 miles) north of Baghdad, March 14, 2007. [Reuters]

The explosion occurred at 7:30 a.m. as the bus was carrying employees of a state-owned car company to work in Iskandariyah, 30 miles south of Baghdad. The city is in the so-called "Triangle of Death" because of relentless attacks by Sunni insurgents.

The bombing came a day after gunmen attacked a Sunni mosque in the city, causing no casualties but severely damaging the building.