Baghdad, Iraq ? American hostage Thomas Hamill was sitting in a mud shack with a bullet wound festering in his arm when he heard the rumble of Army Humvees and made a break for it. He stumbled into the desert and waved his shirt to get the attention of passing soldiers.

“He was yelling, ‘I’m an American, I’m an American POW,”‘ recalled Lt. Joseph Merrill, a member of an Army platoon that happened upon the grizzled Mississippi contract worker north of Baghdad on Sunday morning.

As Hamill whooped, soldiers radioed in that a farmer was approaching them. Hamill tripped and fell a few times, rising each time. Soon the soldiers understood he was shouting in English and somebody recognized the hostage, Merrill said.

The 43-year-old truck driver was taken Monday to the U.S. military’s Landstuhl Regional Medical Center in Germany for treatment and a reunion with his wife, Kellie, expected today.

Hamill’s whereabouts had been unknown since he was seen in a dramatic video taken after guerrillas captured him during an April 9 ambush on a supply convoy. Gunmen shot up and set fire to the vehicles on the outskirts of Baghdad. Hamill was wounded in the right forearm.

Some three weeks later, Hamill’s captors took him to a mud farmhouse near the town of Balad, 50 miles north of Baghdad.

The door to Hamill’s room was a piece of sheet metal propped up by a board. Hamill, of Macon, Miss., told soldiers he believed a single guard was nearby, but out of sight.

About 11:15 a.m. Sunday (2:15 a.m. CDT), soldiers from the New York National Guard’s 2nd Battalion, 108th Infantry Regiment drove their Humvees along a stretch of road next to a broken oil pipeline.

When Hamill heard the Humvees, he knocked over the sheet metal, pried open the doors of the shack and ran about 300 yards toward the convoy.

“He said he thought this was the only chance he had, so he made a run for it,” said Merrill, of Deposit, N.Y. “He said he didn’t know if the guard was there or not.”

Hamill told soldiers he’d been well treated by his captors, who gave him a rudimentary medical kit, a box of cookies and an oil lamp.

Hamill’s cousin, Jason Higginbotham, told CNN that Hamill had tried to escape before but went back to his captors, apparently unnoticed, after finding himself in the desert without food or water and fearing he wouldn’t survive.

“He escaped one time about three days earlier and he was out in the middle of the desert. A helicopter came over and he tried to flag it down, but they evidently didn’t see him,” Higginbotham said.

“They were taking fairly good care of him, so he went and put himself back in captivity without them knowing.”