Earlier on thursday, the day's first suicide car bombing killed sixteen policemen and five civilians, signalling a new round of bomb violence one day after residents suffered through Baghdad's bloodiest day of the war.
Three civilians were killed when a roadside bomb struck a ministry of industry bus in eastern Baghdad. Thirteen were injured in the attack, said police Lieutenant Col. Ahmed Abbod.
The United States and Iraqi troops in Ramadi, an insurgent stronghold 115 kilometres west of Baghdad, came under mortar attack on Thursday morning as armed militants roamed the streets, police Capt. Nasir Alusi said. Al-Qaeda in Iraq said it launched the attacks on Wednesday. There was no immediate claim for bombings on Thursday.
Al-Qaeda's leader in Iraq, Abu Musab al-Zarqawi, purportedly declared "all-out war" on Shiites, Iraqi troops and the government in an audiotape posted on Wednesday on an Internet site known for carrying extremist Islamic content.
On Wednesday, more than a dozen co-ordinated bombings ripped through Baghdad, killing 160 people and wounding 570. Many of the victims were day laborers lured by a suicide attacker posing as an employer.