Guerrillas launched a brazen attack Thursday on an Iraqi civil defense outpost visited by Gen. John Abizaid (search), commander of all U.S. forces in the Middle East. Abizaid and his party escaped injury in the gun battle.

Just moments after a convoy carrying Abizaid and his party pulled inside the cinderblock walls at the headquarters of the Iraqi Civil Defense Corps (search) in this city west of Baghdad, an explosion rang out. Seconds later, two more explosions were heard near the rear of the compound, and U.S. soldiers responded with a barrage of rifle and machine gun fire.

Several attackers fired three rocket-propelled grenades (search), and another pelted the party with small arms fire from a nearby mosque. The gun battle lasted about six minutes.

No U.S. soldiers and no one in Abizaid's party were injured, but Iraqis in the city said two people were killed when the Americans sprayed the area with automatic fire. Video taken by Associated Press Television News showed civilian cars with bullet holes and blood stains.

"We heard from a citizen that someone was killed in a car," Fallujah police Lt. Omar Ali said. "We sent our patrols to the site of the incident. When we arrived there, we saw American forces. They took two dead, put them in a vehicle and left."

His account could not be independently confirmed.

Abizaid was accompanied by Maj. Gen. Charles Swannack, commander of the 82nd Airborne Division. After the gun battle, Abizaid and Swannack canceled plans to walk into the city and instead returned to a U.S. military base near here.

A defense official in Washington, speaking on condition of anonymity, said it was likely that the insurgents had been tipped off to the presence of the senior general.

However, U.S. officials, briefing reporters at military headquarters in Baghdad, said they were not prepared to make such a link. Brig Gen. Mark Kimmitt noted similar attacks have happened before in Fallujah.

"Whether we can directly link this attack to any foreknowledge that General Abizaid and General Swannack would be there is I think a bit of a leap that we're not prepared to make at this time," he said.

Kimmitt issued a statement saying: "Today at 1330 (1:30 p.m. local time) in Fallujah, Gen. Abizaid and Gen. Swannack were visiting an Iraqi Civil Defense Corps battalion headquarters compound when three rocket propelled grenades were fired at their convoy from rooftops in the vicinity. No soldiers or civilians were injured and both coalition and Iraqi civil defense soldiers returned fire and pursued the attackers. A local mosque was thought to be harboring the attackers and Iraqi Civil Defense Corps soldiers conducted a search of the mosque without result."

Kimmitt said Swannack reported that the attack was believed due to "a small number of personnel unrepresentative" of most of the people of Fallujah.

In response to a question of whether there had been a security lapse, Kimmitt said, "I would challenge your assertion that there was foreknowledge of this, that General Abizaid and (Major General Charles) Swannack would be there."

"I would like to say this is the first time we've stood at this podium and reported rocket attacks in Fallujah. It is not," Kimmitt added.

Abizaid left in a convoy of Humvee utility vehicles, soldiers of the 82nd Airborne's 505th Parachute Infantry Regiment. He appeared unfazed. Speaking in Arabic to one member of the Iraqi security force after the gunfight, the general asked about the attack and was told, "This is Fallujah. What do you expect?"

Later, after he returned to the U.S. base, Abizaid told a reporter, "This is an area where there are plenty of former regime elements out there, willing to fight." Abizaid then flew on to Qatar, as scheduled.

In Washington, Defense Secretary Donald H. Rumseld said he didn't know what led to the attack. Talking to reporters after testifying on Capitol Hill, he said, "I have no idea what initiated that attack."

Rumsfeld said he could only conjecture about the motives of the attackers, including the possibility they were paid insurgents.

"There's no question that there are former regime elements who think they would like to take the country back," he said, "but they're not going to."

Abizaid was tapped as Central Command chief after Gen. Tommy Franks retired after the ouster of President Saddam Hussein.