For the first time in more than five years, a prominent Palestinian Arab activist, Sami Al-Arian, is free from jail.

His respite from jail may not last long: The former college professor faces a second round of criminal charges in his lengthy legal battle with federal prosecutors.

Al-Arian had been in government custody since he was charged with being the leader in America of the Palestinian Islamic Jihad more than five years ago. He was not convicted at trial, although he subsequently pleaded guilty to lending aid to that group and received a sentence of 57 months. Al-Arian’s incarceration has outlasted that sentence, as prosecutors first used civil contempt charges, then criminal charges, and finally an immigration proceeding to lengthen his stay behind bars.

Al-Arian was released yesterday into the custody of his family, a daughter, Laila al-Arian, told The New York Sun.

“We are very grateful and happy to spend time with my father and to finally be reunited,” she said, speaking by telephone from her home in Northern Virginia. Ms. Al-Arian declined to put her father on the phone.

She said the decision, by Judge Leonie Brinkema, to approve her father’s release, “shows that all along my father hasn’t been a flight risk, nor a threat, and that he’s a respectable member of society who deserved to be released.”

She added: “We hope that the next step will be his permanent freedom.”

In June, prosecutors in Alexandria, Va., charged Al-Arian with criminal contempt for refusing to provide testimony to grand juries that were investigating financial transfers involving a think tank called the International Institute Islamic Thought. Judge Brinkema has put Al-Arian’s trial on those charges on hold until the Supreme Court announces whether it will taken an appeal over whether Al-Arian is protected from testifying by his plea agreement in the earlier case.