The official, speaking to AFP on condition of anonymity, said there were indications the Iraqis had tried to create an international diplomatic incident by altering the route of the convoy so it would pass through a contested area west of Baghdad instead of a relatively quiet section of road.

"It looks like it was a trap set by the Iraqis," the official said.

The official said the Russians had given US diplomats precise details of the description and number of vehicles in the convoy, the people in them as well as the exact route they would be taking out of the Iraqi capital.

This information was then passed on to US military commanders in order to prevent the convoy from facing fire from coalition forces who have surrounded Baghdad and are advancing on the center of the city, the official said.

"We had been in touch for several days with the Russians about the withdrawal of their personnel," the official said. "We had detailed information about the vehicles, the personnel and the route they were going to follow.

"All of this was passed on to the commanders in the field so they would know to let it pass," the official said.

"It seems the Iraqis may have told them to take a different route than they told us because we didn't have anyone in the area they were supposed to be in," the official added.

The official said last-minute changes to the route might explain why US Central Command at first maintained there were no coalition troops in the area where the convoy was traveling when it was hit.

As it turned out, the convoy carrying Russian ambassador to Iraq Vladimir Titorenko and other embassy staff came under fire shortly after it left Baghdad, injuring the envoy and at least four others.

According to eyewitness accounts, the convoy was caught in a crossfire between US and Iraqi soldiers although the reports were not clear as to which side started shooting first.

The US official said the first reports from the US military indicated that the Iraqis had fired first but stressed that the investigation into the incident was still in its preliminary stages.

"From what we can tell, We had guys coming into the area, the convoy coming into the area and the Iraqis were waiting," the official said. "When the vehicles came by, the Iraqis started shooting."

"It's all very unclear, but it was certainly not our intention to whack this guy (the Russian ambassador)," the official said. "That's why we think the Russians followed a different route."

Whatever the cause of the attack, it has further strained already tense ties between Washington and Moscow and just hours after the attack US Secretary of State Colin Powell called his Russian counterpart Igor Ivanov to assure him a full investigation into the matter was underway, the State Department said.

In addition, the incident was discussed in Moscow by visiting US national security advisor Condoleezza Rice who arrived there on Sunday shortly after the incident took place.

SPACE.WIRE