U.S. death toll in Iraq tops 500
Blast north of Baghdad kills 3 American soldiers, 2 Iraqis
CNN's Michael Holmes on the rising U.S. death toll in Iraq and an upcoming troop redeployment.
The U.S. military is investigating allegations of abuse against detainees in Baghdad.
CNN's Robin Oakley on a potentially damaging report facing British Prime Minister Tony Blair.
A report accuses the U.S. Army of criminal negligence in journalists' deaths.
TAJI, Iraq (CNN) -- The number of U.S. troops killed in the Iraq war passed 500 on Saturday when three American soldiers died in a roadside bombing north of Baghdad.
A patrol was sweeping a rural area for bombs when one detonated on a road west of Taji, about 19 miles (30 kilometers) north of the Iraqi capital, according to a statement from the 4th Infantry Division.
The explosion split open the gun turret of the patrol's Bradley fighting vehicle, knocked the 26-ton armored vehicle on its side and started a fire, military sources said.
In addition to the Americans, two members of the Iraqi Civil Defense Corps were killed. The Bradley's gunner and commander were injured, the sources said. The wounded soldiers were taken to a Baghdad hospital, according to the military.
On Friday, a U.S. soldier died from a "nonhostile" gunshot about 75 miles (120 kilometers) south of Baghdad, according to the U.S.-led coalition.
With the latest casualties, 501 U.S. troops have been killed in Iraq, including 346 in hostile action. Most of those deaths have come since President Bush declared the end of major combat operations May 1.
After Saturday's blast, a quick-reaction force secured the area and detained three Iraqis fleeing in a white truck carrying bombmaking materials, the 4th Infantry Division said.
"The enemy can try to do this to us every single day, but it's not going to change our resolve or desire to see things through to the very end," Lt. Col. Richard French said.
U.S. to cut troops
The United States will cut its manpower and rely more heavily on lighter transport equipment over the next few months in an effort to adapt to the protracted low-level guerrilla insurgency largely centered in the so-called Sunni Triangle.
The Sunni Triangle is the area north and west of Baghdad, home to Saddam loyalists and Baath party members, in which opposition to the U.S.-led coalition has been the greatest.
A senior U.S. military officer said Saturday that the rotation of men and materiel, which is being called "Operation Iraqi Freedom 2," will allow the coalition to focus on "smaller engagements" with "smaller numbers."
The officer said the U.S. troop strength will drop from 130,000 now to 105,000 by June, and that those will soldiers will all be transferred into Iraq.
"While there may be a reduction in the numbers, it's not a reduction in our capability," the officer said.
The U.S.-led coalition will reduce the number of tanks and helicopters. It will increase the numbers of Humvees, armored personnel carriers and light-armored vehicles, and will increase intelligence-gathering capabilities.
The army is reducing its deployment of M1A1 main battle tanks from 600 to 150 and is removing its 94 multiple rocket launchers. The number of Apache attack helicopters will be reduced from about 150 to a force of 100, which will include a number of the lighter Cobras.
The number of UH-60 Black Hawk copters will be reduced from 350 to 200. The number of howitzer cannons will also be reduced.
The number of infantry vehicles will rise from 600 to 850. Troops will be using 323 of the Army's new Strykers -- eight-wheeled, medium-armored vehicles with room for 11 people.
There will be changes in the organizational setup in the northern, central, western and Baghdad sectors.
The 1st Marine Expeditionary Force will move into the turbulent area west of Baghdad, taking over patrols from the 82nd Airborne Division. That area includes places like Ramadi and Fallujah.
The 4th Infantry Division and the 173rd Airborne Brigade patrolling north of Baghdad around Tikrit and Kirkuk will be replaced by two brigades of the 1st Infantry Division, a brigade of the 25th Infantry Division and the 30th Infantry Brigade of the North Carolina National Guard.
A Stryker Brigade will replace the 101st Airborne Division in northwestern Iraq. The number of troops is being cut to about half of the 19,000 there.
In Baghdad, the 1st Armored Division will be replaced by the 1st Cavalry Division and the 39th Infantry Brigade of the Arkansas National Guard.
The changes don't affect the 25,000 troops from other countries, and Iraqi fighters are not moving in to replace departing troops. The plan will be reviewed by Iraq after the coalition hands over power to a new government July 1.
• Lt. Gen. Ricardo Sanchez, commanding general of U.S. and coalition forces in Iraq, has ordered a criminal investigation into allegations of prisoner abuse by U.S. troops in Iraq, Pentagon officials said Friday. Officials said the probe at a detention facility encompasses more than one allegation. The allegations included kicking prisoners in the groin and twisting a prisoner's injured arm.
• Administration sources said the United States hopes to win a strong statement from U.N. Secretary-General Kofi Annan backing the U.S. transition plan as well as a commitment to send a U.N. team to Iraq to assist with the effort. L. Paul Bremer, the U.S. civilian administrator in Iraq, said the United Nations has a "vital role" to play in postwar Iraq. (Full story)
CNN's John King, Sheila MacVicar, Karl Penhaul, Barbara Starr and Alphonso Van Marsh contributed to this report.