WASHINGTON - Pat Tillman, the former professional football player killed in Afghanistan, has been awarded the Silver Star for leading his team to the rescue of comrades caught in an ambush.

Tillman was shot and killed while fighting "without regard for his personal safety," the Army said in announcing the award.

The Silver Star, awarded for gallantry on the battlefield, is one of the most distinguished military honors.

On Thursday the Army announced that Tillman had been posthumously promoted from specialist to corporal. He was assigned to A Company, 2nd Battalion, 75th Ranger Regiment, based at Fort Lewis, Wash.

In announcing the Silver Star award, the Army Special Operations Command, of which the Rangers are a part, provided the most specific description thus far of what happened to Tillman.

His platoon was split into two sections for what officials called a ground assault convoy. Tillman was leader of the lead group. The trailing group received mortar and small arms fire, and because of the cavernous terrain the group had no room to maneuver out of the "kill zone."

Tillman's group was already safely out of the area, but when the trailing group came under fire he ordered his men to get out of their vehicles and move up a hill toward the enemy location.

As Tillman crested the hill he returned fire with his M249 Squad Automatic Weapon, a light-weight machine gun.

"Through the firing Tillman's voice was heard issuing fire commands to take the fight to the enemy on the dominating high ground," the award announcement said. "Only after his team engaged the well-armed enemy did it appear their fires diminished."

"As a result of his leadership and his team's efforts, the platoon trail section was able to maneuver through the ambush to positions of safety without a single casualty," the announcement said.

The announcement gave no other details of how Tillman was killed.

At least one other soldier in Tillman's unit apparently was wounded. Gen. John Abizaid, the commander of all forces in Afghanistan and Iraq, told reporters that he spoke Thursday in Afghanistan with the lieutenant who was Tillman's platoon leader.

"He was still nursing a large number of wounds that he sustained in that firefight where Pat Tillman lost his life," Abizaid said Friday.

Abizaid said he asked the lieutenant about Tillman.

"He said, 'Pat Tillman was a great Ranger and a great soldier. And what more can I say about him?' "

Tillman, who was 27, walked away from a three-year, $3.6 million contract offer from the Arizona Cardinals to join the Army in 2002.