CAIRO, Egypt -- In a grisly reminder of the deaths of five Americans in a helicopter crash on Tuesday, an insurgent group posted a video on an Islamic Web site that claimed to show the wreckage and two bodies.

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The Associated Press reported that it carried the logo of the 1920 Revolution Brigades, a known Sunni militant group. It showed wreckage of a helicopter with bricks scattered around it. The naked bodies of two men, one with gray hair and the other with dark hair, were seen near the wreckage.

Iraqi and U.S. officials said earlier that four of the five Americans who died were killed on the ground, in execution-style shootings in the backs of their heads.

The two bodies shown in the video had no visible gunshot wounds to the heads or any other visible wounds.

The helicopter, owned by Blackwater USA, was shot down after racing to help a U.S. Embassy ground convoy that had come under fire in the Sunni neighborhood. A second helicopter also was hit, but there were no casualties among its crew, a Washington official said.

Mortar Shells Slam Into Green Zone

A huge explosion rocked central Baghdad shortly before sunset, local time, on Thursday, and two mortar shells slammed into the heavily fortified Green Zone.

The Green Zone houses the U.S. Embassy and other key government buildings. The public address system inside the zone could be heard warning in English that people should take cover. The address said, "This is not a drill."

A suicide bomber struck in the central neighborhood of Karradah, the second to hit the area in three days. At least three policemen were among the 26 dead from the latest bombing, and 54 people were wounded, police and hospital officials said.

News of the attacks came as members of a Senate committee who voted against President George W. Bush's Iraq plan said they are wary of pouring more money into rebuilding while the security situation is so dire.

"I want you to know that I am not inclined to support any additional funding in this area without strong assurances that this sort of mismanagement has been alleviated," said Sen. Jim Webb, D-Va.

A full Senate vote on the resolution could come as early as the week of Feb. 5, Democratic leaders said Thursday.

Bush said the troops are needed to provide security for rebuilding efforts. As part of his new strategy, Bush pledged an additional $1.2 billion and said the Iraqi government designated $10 billion.

In a string of operations across Iraq over the past four days, Iraqi and coalition forces detained 43 suspected terrorists, found several weapons caches, stopped an illegal checkpoint, and freed three captives, military officials reported.

U.S. Tallies Dead

A soldier was killed when an improvised explosive device detonated near a patrol northwest of Baghdad Thursday, officials reported.

Three other soldiers were injured in the blast. The dead soldier's name is being withheld until his family is notified.

In other news, the Defense Department released the identities of 11 soldiers and four Marines killed recently supporting Operation Iraqi Freedom.

Army Staff Sgt. Michael J. Wiggins, 26, of Cleveland, Ohio, died Jan. 23 in Balad, Iraq, of a non-combat-related injury. He was assigned to the 79th Explosive Ordnance Disposal Battalion in Fort Sam Houston, Texas.

Marine Sgt. Gary S. Johnston, 21, of Windthorst, Texas, died Jan. 23 during combat operations in Anbar province. Johnston was assigned to the 3rd Reconnaissance Battalion, 3rd Marine Division, 3rd Marine Expeditionary Force in Okinawa, Japan.

Marine Lance Cpl. Andrew G. Matus, 19, of Chetek, Wis., died Jan. 21 from wounds received during operations in Anbar province. Matus was assigned to the Battalion Landing Team 2nd Battalion in the 1st Marine Expeditionary Force in Camp Pendleton, Calif.

Marine Cpl. Darrel J. Morris, 21, of Spokane, Wash., died Jan. 21 during combat operations in Anbar province. Morris was assigned to the 2nd Battalion, 10th Marine Regiment, 2nd Marine Division, 2nd Marine Expeditionary Force at Camp Lejeune, N.C.

Marine Lance Cpl. Emilian D. Sanchez, 20, of Santa Ana Pueblo, N.M., died Jan. 21 from wounds received during combat in Anbar province. He was assigned to the Battalion Landing Team 2nd Battalion, 4th Marine Regiment, 15th Marine Expeditionary Unit (Special Operations Capable), 1st Marine Expeditionary Force at Camp Pendleton, Calif.

Army Sgt. Jonathan P. C. Kingman, 21, of Nankin, Ohio, died Jan. 20 near Baji, Iraq, of wounds suffered when an improvised explosive device detonated near his vehicle. He was assigned to the 41st Engineer Company, 1st Engineer Battalion, 1st Brigade Combat Team, 1st Infantry Division at Fort Riley, Kan.

Army Sgt. Sean P. Fennerty, 25, of Corvallis, Ore.; Army Sgt. Phillip D. McNeill, 22, of Sunrise, Fla.; Army Spc. Jeffrey D. Bisson, 22, of Vista, Calif.; and Army Spc. Toby R. Olsen, 28, of Manchester, N.H., died Jan 20 in Karma, Iraq, of wounds suffered when an IED detonated near their Humvee. The soldiers were assigned to the 3rd Battalion, 509th Infantry (Airborne), 4th Brigade Combat Team, 25th Infantry Division in Fort Richardson, Alaska.

Army 1st Lt. Jacob N. Fritz, 25, of Verdon, Neb.; Army Spc. Johnathan B. Chism, 22, of Gonzales, La.; Army Pfc. Shawn P. Falter, 25, of Cortland, N.Y.; and Army Pvt. Johnathon M. Millican, 20, of Trafford, Ala., died Jan 20 in Karbala, Iraq, from wounds suffered when their patrol was ambushed while conducting dismounted operations. The soldiers were assigned to the 2nd Battalion, 377th Parachute Field Artillery Regiment, 4th Brigade Combat Team, 25th Infantry Division in Fort Richardson, Alaska.

Army Pfc. Ryan J. Hill, 20, of Keizer, Ore., died Jan. 20 in Baghdad of wounds suffered when an IED detonated near his Humvee. Hill was assigned to the 1st Battalion, 26th Infantry Regiment, 2nd Brigade Combat Team, 1st Infantry Division in Schweinfurt, Germany.

Sgt. Michael M. Kashkoush, 24, of Chagrin Falls, Ohio, died Jan. 23 from wounds received while conducting combat operations in Al Anbar province, Iraq. Kashkoush was assigned to 3rd Intelligence Battalion, III Marine Expeditionary Force, Okinawa, Japan.

Spc. Brandon L. Stout, 23, of Grand Rapids, Mich., died Jan. 22 in Baghdad, Iraq, of wounds suffered when an explosively formed projectile detonated near his vehicle. Stout was assigned to the 46th Military Police Company, Michigan Army National Guard, Kingsford, Mich.

Staff Sgt. Jamie D. Wilson, 34, of San Diego, Calif., died Jan. 22 in Fallujah, Iraq, from wounds suffered while conducting security operations in Karmah, Iraq. Wilson was assigned to the 3rd Battalion, 509th Infantry Regiment (Airborne), 4th Brigade Combat Team, 25th Infantry Division, Fort Richardson, Alaska.