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Marine Cpl. Wassef Ali Hassoun (search) will be moved out of Lebanon to a U.S. base in Europe "in the near future," military sources told FOX News late Thursday.

The sources said it is likely, but not yet finalized, that he will be moved to the airbase in Rammstein, Germany, within 24 hours.

The officials added that Rammstein was only Hassoun's "most likely" next destination, but there are other U.S. military facilities, perhaps in Italy, that could handle the next steps in his case — a complete medical exam and a comprehensive debriefing by military investigators, who want to know exactly what he has been up to in the course of a very mysterious 3 1/2 weeks.

The U.S. Marine, who was rumored to have been kidnapped and beheaded, turned up alive and well at the U.S. Embassy in his home country of Lebanon on Thursday, though how he got there remained unknown.

The Navy was investigating whether the abduction of Hassoun — who disappeared 18 days ago from his base near the volatile city of Fallujah, Iraq — was all just a hoax.

Hassoun contacted U.S. officials, who arranged to pick him up Thursday afternoon in Beirut, State Department (search) spokesman Richard Boucher said in Washington.

At nearly the same time, a gunfight broke out between members of Hassoun's clan in his home city of Tripoli and business rivals who called them American collaborators because Hassoun joined the Marines. Two people were killed.

Confusion had surrounded the fate of the 24-year-old, Lebanese-born Hassoun since a dramatic videotape broadcast on Arab television June 27 showed him with his eyes covered by a white blindfold and a sword hanging over his head.

His reported capture, claimed by a group calling itself "Islamic Response," came during the tense run-up to the U.S. transfer of sovereignty to an interim Iraqi government on June 28, a period of increased abductions and killings of foreigners and attacks on U.S. forces.

A statement on an Islamic militant Web site Saturday claimed that Hassoun had been beheaded, as were an American businessman and a Korean translator in Iraq and an American contractor in Saudi Arabia. The next day, a statement on another Islamic Web site denied he had been killed.

In the latest twists to Hassoun's story, there was speculation he might have deserted his base and headed to Lebanon when he was abducted. The Navy was investigating whether the entire kidnapping might have been part of a hoax.

"I don't think they're ruling that out. It would be fair to say they're not ruling that out," a Marine spokesman, Maj. Nat Fahy, told The Associated Press.

A spokesman for the Bahrain-based U.S. Navy's 5th Fleet said the "matter is under investigation by Naval Criminal Investigative Service" and referred further questions to Washington.

It was unclear how Hassoun, who had been working as a translator in Iraq, reached Lebanon and how he made contact with American officials. An embassy spokeswoman, Elizabeth Wharton, said the Marine arrived at the fortified embassy, located in a hilly Beirut suburb, accompanied by relatives.

Boucher said he had no information on Hassoun's immediate plans, and that his military status would be up to the Defense Department.

A neighbor in Tripoli, who refused to give his name, said Hassoun left Lebanon for Utah in 1999, joining his parents and brother. Educated in Lebanon at American schools, he joined the Marines in 2001 and had not been back to Lebanon since. He married an American woman two years ago, but they divorced.

The neighbor and a distant cousin, Abdullah Hassoun, said the Marine wed a cousin in Lebanon by proxy several months ago. His father signed the marriage contract for him, which is permitted by Islam.

The Marines said Hassoun disappeared June 20 on "unauthorized leave" but changed his status to "captured" after the videotape of him blindfolded surfaced a week later.

On Monday, after the conflicting reports of his killing, the group Islamic Response issued a statement broadcast on the satellite network Al-Jazeera saying it had Hassoun and that he was safe.

Earlier, the captors claimed Hassoun was romantically involved with an Arab woman, and that they lured him away from his Marine base and captured him.

There also were earlier reports from U.S. military officials, who spoke on condition of anonymity, that Hassoun might have been trying to get to Lebanon when he was captured. Some officials reportedly said the Marine fled his camp after seeing a comrade killed by a mortar shell; others indicated he was indeed lured away and kidnapped.

For Hassoun to reach Lebanon from Iraq, about 500 miles away, he would have to travel through Syria, which borders Iraq's western Anbar province. His unit, the 1st Marine Expeditionary Force (search), is based at the border.

Hassoun's brother, Sami, refused to comment when contacted Thursday by the AP. On Tuesday, he told AP someone had visited the family in northern Lebanon and told them his brother was free and well.

A Lebanese government official said Wednesday the kidnappers released Hassoun after he promised not to return to the U.S. military.

Two FBI agents had met with the Hassoun family in Utah for about 20 minutes Wednesday. The agents were not there to deliver any news to the family, but instead were sent to determine where the family was getting its information about Hassoun's whereabouts, agent Kelly Kleinvachter said.

Earlier Thursday, no overt signs of joy or preparations to welcome Hassoun could be seen at the family residence in Tripoli, an apartment in the low-income Abu Samra district.

The shooting incident Thursday happened in another neighborhood, Lebanese security and hospital officials said. They said the two people killed and three wounded were not part of the Hassoun clan, which is made up of about 1,000 people.

The security officials said the gunbattle stemmed from an old dispute about the location of street vendors outside a shop owned by a Hassoun clan member.

Witnesses said the vendors provoked the Hassoun shopkeeper with taunts that his relatives were American agents. The shopkeeper ran inside, came out with a rifle and opened fire.

The Hassoun clan member fled, leaving his shop open. A relative of one of the victims threw a grenade into the shop, setting it on fire, the witnesses said, speaking on condition of anonymity.

Tripoli, Lebanon's second-largest city, is a predominantly Sunni Muslim town where anti-American sentiments run strong.

Fox News' Ian McCaleb and The Associated Press contributed to this report.