BAGHDAD, Iraq - Two suicide car bombs exploded in a central Baghdad square Saturday, killing 15 people, including two Americans, the U.S. Embassy said.

Iraqi officials said about 30 people also were wounded in the attack in Tahrir Square, where shops were damaged and cars were burned by the blasts.

The remains of mutilated bodies were seen lying in the street as fire trucks fought the blaze, which sent a large plume of black smoke up into the sky.

The attack was part of a surge in violence that has killed more than 275 people - many of them Iraqi soldiers and police - since Prime Minister Ibrahim al-Jaafari's new government was sworn in April 28.

On Friday, car bombs struck a market and a police bus outside the capital, killing at least 25 people. A dozen bodies also were uncovered in a garbage dump on the outskirts of Baghdad - some of them blindfolded and shot execution-style.