An American volunteer was freed unharmed late Wednesday after being held for a day by Palestinians in the West Bank city of Nablus in a bizarre kidnapping.

Michael Leighton Phillips, 24, was brought to the home of former Nablus mayor Ghassan Shakaa. He was accompanied by about 20 gunmen from the Al Aqsa Martyrs' Brigades, who claimed credit for freeing him. Al Aqsa is a violent group linked to the Fatah movement, headed by Palestinian President Mahmoud Abbas.

Even after the hostage was freed, it was unclear who had kidnapped him or what they wanted.

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The Al Aqsa men said they spotted a suspicious car and stopped it, finding Phillips and four of his captors inside. They freed the American, but the kidnappers escaped, they said, adding that they did not know who the kidnappers were.

Looking shaken but uninjured, Phillips, a volunteer teacher, said he hoped to remain in Nablus. "I don't want to leave," he told reporters. He said he was kidnapped on Tuesday.

Phillips, from near New Orleans, was seated at a table as news cameramen photographed him. He thanked the people who helped win his freedom. Later he talked by telephone to his family and to Abbas.

Standing near Phillips, local Fatah leader Jamal Tirawi criticized the Hamas-led government over the kidnapping, calling on Interior Minister Said Siyam of Hamas, who heads security services, to "do his job."

Fatah and the Hamas have been in a power struggle since the Islamic movement ousted Fatah from power in January elections.

Tirawi said lawlessness could not take over. "This will not be Lebanon, this will not be Iraq," he said.

Rumors of the kidnapping swept through the West Bank early Wednesday. A previously unknown group calling itself Ansar al-Sunna claimed responsibility and sent a foreign news agency a photocopy of his passport.

Phillips was a volunteer with Project Hope, a Canada-based group. Phillips taught English in refugee camps near Nablus, according to Samah Atout, West Bank manager of Project Hope.

Jeremy Wildeman, executive director of Project Hope, said from his office in Toronto that they had not heard from Phillips since Tuesday. He said Phillips, from New Orleans, graduated in May from George Washington University and had been volunteering as an English teacher on the West Bank ever since.

Wildeman said Project Hope was based in the West Bank but carries out its fundraising and technical support in Canada and Britain. He said they mostly teach English and French to students who suffer from traumatic stress disorders.

He said the volunteers typically work for three-month stints, but that Phillips asked to stay another three months.

"Michael was more of an extreme. He quite enjoyed his experience and he didn't want to leave," he said.

George Washington University spokeswoman Tracy Schariot said Phillips, from the New Orleans suburb of Mandeville, graduated last year with a bachelor's degree in international affairs.

One call to the family's home in Mandeville was picked up without any answer; the next was not answered.

Foreigners have been kidnapped and held briefly in Nablus in the past, then released unharmed. The most recent case was in February, during the storm over the Danish caricatures of the Prophet Mohammed, when a German volunteer was abducted and held for several hours.