A roadside bomb blast Wednesday at Baghdad's largest and oldest wholesale market district killed at least 24 people and injured 35, bringing the total killed around Iraq to 39 people, police said. The blast occurred at 9:50 a.m. (0550 GMT) at the Shurja commercial center, police Lt.'s Mohammed Khayoun and Bilal Ali Majid said. Shurja is one of Iraq's largest markets, where wholesalers use warehouses, stalls and shops to sell food, clothing and house products to businessmen and shoppers. A maze of streets and stalls, the area is usually teeming with vendors selling everything from satellite dishes to spices. Earlier, an explosives-rigged bicycle detonated near an army recruiting center in a city south of Baghdad on Wednesday, killing at least 12 people and wounding 28, police said. In downtown Baghdad, three police officers were killed and 14 people were injured when twin bombs - including one planted in a car - struck a police patrol as it drove by a line of vehicles waiting in a line for gasoline at a filling station. In central Hillah, about 95 kilometers (60 miles) south of Baghdad, a man posing as a potential army recruit planted the explosives-rigged bicycle early in the morning outside the recruiting center, said police Lt. Osama Ahmed. The man walked off as volunteers gathered outside to sign up for the army, and the bomb exploded at about 8:00 a.m, Ahmed said. Hillah was the site of one of the worst bomb attacks in Iraq, when a suicide car bomber in Feb. 2005 killed 125 national guard and police recruits who were lined up to take physical tests. In another incident in 2005, a bomb explosion killed 60 civilians who were lining up to apply for police jobs in the Kurdish city of Irbil in northern Iraq. Insurgents have often targeted Iraqi army and police volunteers as they line up outside recruiting stations, as a way to discourage people from joining the security services and keep the military and police weak.