A suicide bomber blew up his car outside a hospital south of Baghdad today as US troops were handing out food to children, killing 30 people and injuring about 40, including four Americans.

Rebels reeling from the loss of their base in Fallujah struck back with car bombings and a rocket attack on Baghdad’s Green Zone as a US official admitted that security in some areas was deteriorating so badly “it would now be difficult” to hold elections there.