Reports say multiple car bombs have gone off, two of them near the mayor's office. US troops trying to get to the scene were also attacked by rebels.

Three police stations were also hit in the violence, wounding and killing a number of policemen.

There are also reports that US troops are getting ready for a big attack on the rebel held city of Falluja.

More than 40 people were hurt in the attacks in Samarra.

Iraqi officials and police are often targeted by rebels who don't like the fact they are working with the US, who they think should leave the country.

On Friday night, locals were told to leave Falluja to prepare for strikes by US planes.

Meanwhile, Kofi Annan, the head of the United Nations, has asked US and Iraqi leaders to think again before attacking the area.