Suicide bombing kills 23 near coalition safe zone
Bremer: Plans to hand over power to Iraqis unchanged
U.S. soldiers inspect vehicles destroyed in the suicide bombing Sunday in Baghdad.
CNN's Sheila MacVicar on the Baghdad suicide bombing that killed at least 23 people.
Some of the bomb victims get treatment at a Baghdad hospital.
The truck bomb contained about 1,000 pounds of explosives.
Concrete barriers provide some protection against suicide bombers.
BAGHDAD, Iraq (CNN) -- A suicide bombing outside the compound of the U.S.-led occupation authority in Baghdad killed at least 23 people, most of them Iraqi civilians trapped in their cars as they were waiting to pass through security checks.
The blast shook buildings miles away from the Green Zone, the heavily fortified area that is home to the Coalition Provisional Authority. More than 60 were wounded.
The truck was laden with about 1,000 pounds of military-grade explosives, a military official said.
A security source told CNN the bomber may have carried eight unsuspecting Iraqis in the back of the vehicle to disguise his intentions, but a military source in Baghdad, citing witness accounts from soldiers, said no day laborers were on the vehicle.
The bombing took place as many Iraqis lined up at security checkpoints near the gate to start their workday or apply for a job at the coalition headquarters.
Traffic packed a main intersection outside the entrance at the time of the blast, and many of the Iraqis killed were in their vehicles waiting to pass through a checkpoint, a U.S. military spokesman said.
"We're hearing that the fireball was huge and that they didn't have a chance," the unnamed spokesman said, referring to the Iraqis inside the cars.
The force of the blast destroyed at least six vehicles, Capt. Jason Beck of the 1st Armored Division said.
One Iraqi was able to pull two people from a burning car but was unable to save the other two because of the intense heat.
An Iraqi driver who survived the blast said the force sent his car into the air, landing about 100 yards away.
"I was driving ... toward the bridge when a car exploded," said Jasim Mohammed, who had a visible injury to his face. "I felt my car going up in the air and landing again. All of a sudden, everything turned red and there was a very strong explosion. "
About 90 percent of the explosion was absorbed by blast barriers, protecting the headquarters from damage, Beck said.
CNN staff said the blast shook their hotel in downtown Baghdad a few kilometers away.
The U.S.-backed Iraqi Governing Council issued a short statement calling the bombing an "obscene crime."
"The terrorists' aim is to spoil the atmosphere of freedom, security and life in general by committing this ugly criminal act this morning near the Republican Bridge, in which many innocent Iraqis were killed," the statement said. "All this is a disgrace pointing to the mass graves of the [former] regime and the alleys of terrorists in and out of Iraq, those that show no value to human life."
Half-ton of explosives
U.S. Brig. Gen. Mark Hertling of the 1st Armored Division said the truck was carrying 1,000 pounds of military-grade, plastic explosives when it tried to enter "Assassin's Gate" -- the northern entrance to the Green Zone -- shortly before 8 a.m. (12 a.m. ET).
"We have indications that some of those that were killed were American citizens, U.S. contractors," Brig. Gen. Mark Kimmitt said during a news conference in Baghdad. "We believe the current number at two. We're waiting for firmer confirmation."
Many of the victims were trapped inside their vehicles.
Kimmitt said it had not been possible to identify many of the bodies "because of the nature of the crime."
Three U.S. soldiers were among the wounded, two of whom have been released to duty. Three U.S. civilians were also injured.
Earlier, U.S. military sources said two Department of Defense workers were among the dead but could not specify their occupations or nationalities.
The U.S. military's 28th Combat Support Hospital in the Green Zone reported 20 deaths. Three other people died at al-Karama hospital, according to coalition officials. (Hospital scene)
Bombing ahead of key meeting
The bombing took place a day before the top U.S. civilian administrator in Baghdad was due to meet with U.N. Secretary-General Kofi Annan about the world body's role in Iraq.
L. Paul Bremer condemned the bombing, which he said "was clearly timed to claim the maximum possible number of innocent victims."
Bremer, who will meet with Annan on Monday in New York, said the plan to hand over authority to a new Iraqi government in July "remains unchanged." (Full story)
The United Nations pulled its operations from Iraq after a bombing at its headquarters killed 23 people in August -- including its top envoy to Iraq, Sergio Vieira de Mello, who was also the high commissioner for human rights.
Sunday's blast happened a day after a powerful roadside bomb ripped through a Bradley fighting vehicle north of Baghdad, killing three U.S. soldiers and two Iraqi civil defense forces.
Also Sunday, a roadside bomb detonated in Basra near a British military vehicle, but no one was injured, according to a British military spokesman.
Late Saturday, two Iraqis were killed in Tikrit when an explosive device detonated inside the car they were riding in, military sources said. A third occupant of the white Mercedes has been hospitalized and will be questioned, the sources said. There were no U.S. casualties in the blast.
Meanwhile, a U.S. soldier died Sunday of wounds suffered in a roadside bombing near the central Iraqi city of Samarra on Friday, the U.S. military said. There was no immediate information on the soldier's identity or unit.
With the soldier's death, 502 U.S. troops have been killed in Iraq, including 347 in hostile action. Most of those deaths have come since President Bush declared the end of major combat operations May 1.
CNN's Karl Penhaul, Alphonso Van Marsh, Satinder Bindra, Sheila MacVicar and Michael Holmes contributed to this report.