BAGHDAD - A suicide bomber driving a small truck rigged with explosives blew up near a Baghdad college on Tuesday, killing 18 people in an attack that came just a day after bomb blasts ripped apart two crowded city markets. Police said the bomber detonated in a parking lot between the College of Economic Sciences, a private university in western BaghdadÂ’s residential Iskan district, and a large foodstuff warehouse belonging to the Trade Ministry.The blast in the mainly Shia area set cars ablaze and destroyed a nearby home. Police said some members of the family were among the dead, but a witness said only one girl died. The attack, which also wounded 40 people, followed devastating bombings at two markets on Monday that killed at least 77 people and maimed scores.