A Marine corporal whose reported capture in Iraq has been shrouded in mystery spoke publicly about his experience for the first time today, denying reports that he had deserted his base near Fallujah and insisting that he had been held against his will by insurgents.

Appearing before reporters at the Quantico Marine base in Virginia, Cpl. Wassef Ali Hassoun also expressed solidarity with his fellow Marines, offering words of encouragement to those still serving in Iraq.

"I did not desert my post," said Hassoun, 24, a native of Lebanon, who read from a prepared statement that had been cleared by Marine officials. "I was captured and held against my will by anti-coalition forces for 19 days. This was a very difficult and challenging time for me. Since my release I have been fully participating in the repatriation process."

Wearing camouflage fatigues and looking fit, Hassoun thanked those who supported and prayed for him and "everyone who was looking for me."

He concluded, "I would like to tell all the Marines, as well as those others who are serving in Iraq, to keep their heads up and spirits high. Once a Marine, always a Marine. Semper Fi. Thank you."

Hassoun, 24, who worked as a translator in Iraq, did not take any questions or elaborate on his remarks. After reading his statement, he boarded a van, leaving a Marine public affairs officer to answer reporters' queries.

It was the first time that Hassoun had said anything about the chain of events that became enmeshed in conflicting reports following his June 19 disappearance in Iraq. U.S. military officials said initially that he was on "an unauthorized absence" when he was first reported missing.

Several days later, an Islamic militant group claimed to have captured him and threatened to behead him if the U.S. military in Iraq did not release all its prisoners. Then, on June 27, a videotape broadcast on an Arab network showed Hassoun blindfolded, with a sword held above his head.

A week later, two Arabic Web sites posted statements in which a group called the Ansar al-Sunna Army claimed to have "slaughtered" Hassoun. But the group subsequently denied that it had issued any such statements.

With his fate still in doubt, Hassoun turned up in Beirut and was brought to the U.S. Embassy in Lebanon on July 8. At the time, the Navy was reported to be investigating various aspects of his disappearance, including the possibility that it was part of a kidnapping hoax. A Lebanese official told a news agency that Hassoun's captors had released him after he promised he would not return to the U.S. military.

Hassoun was subsequently flown to a U.S. air base in Germany. He returned to the United States last week and was taken to the Quantico Marine base 36 miles south of Washington, D.C.

Lt. Col. Dave Lapan, a Marine spokesman at Quantico, said Hassoun and a "repatriation team" looking after him would relocate in the coming days to Camp Lejeune, N.C., a major Marine installation. Lapan said the repatriation process would continue indefinitely.

"He has not yet been declared fit for duty, but he can receive the support and services he requires at Camp Lejeune, Lapan said.

Accompanying Hassoun to Camp Lejeune at the young Marine's request, Lapan said, will be one of his brothers, Mohammad Hassoun, who has served as a spokesman for the family at their home in Utah.

Asked about the reported promise to his captors that Hassoun would not rejoin the Marines, Lapan said, "In the time he's been here he has not expressed any reluctance to return to full duty when the time is appropriate."

He said he could not comment on how Hassoun was captured or any other details of his disappearance.

Lapan said that although Hassoun has been dealing with a repatriation team, he has not yet talked to investigators of the Naval Criminal Investigative Service who are looking into his case.

He said Hassoun requested permission to make his statement to the press today because of his concerns "with some of the information that's been out there" about him.

Asked if the Marines were "endorsing" Hassoun's brief explanation of his disappearance or could say whether his captivity was "real or imagined," Lapan said, "We are not in the position at this point to make a judgment either way. We are still gathering facts and information, and until that process is complete, at this point we are supporting our young Marine in bringing him back from a very harrowing ordeal and supporting his return to duty."

Hassoun, who immigrated to the United States from Lebanon in 1999, settled with relatives in Utah before joining the Marines in 2001. His parents and a new wife, whom he married by proxy several months ago, remain in Lebanon.