RAMALLAH, West Bank - Israel released 224 Palestinian prisoners yesterday in a gesture to Palestinian Authority President Mahmoud Abbas. Jubilant detainees waving Palestinian flags jumped on the roof of one of the buses carrying them to freedom.

Separately, Israel expelled an arriving U.N. human-rights envoy, Richard Falk, after accusing him of bias against the Jewish state. Falk has compared Israel to Nazi Germany and accused it of crimes against humanity because of its treatment of Palestinians.

Israel holds more than 8,000 Palestinians, and their fate is an emotionally charged issue. Most Palestinians have had loved ones in prison and view the release of detainees as a test of Israel's willingness to make peace.

Many Israelis balk at the idea of freeing Palestinians involved in violence.

But the scene yesterday brimmed with joy. One prisoner, Abdel Nasser Hussein, 28, was arrested on his wedding day 30 months ago. His fiancee, Alaa Issa, showed up bearing a bouquet of red roses. They embraced.

"It's indescribable happiness," said Hussein, a former member of the Palestinian security forces. After exchanging rings, they walked arm-in-arm, their friends and family clapping and singing a traditional wedding song. They plan to marry in two weeks.

The Israeli prisons service said Hussein was convicted of membership in an illegal organization; possession of weapons, ammunition and explosives; and opening fire. Hussein's brother said he was arrested in June 2006 on charges of firing at Israeli soldiers during raids in Ramallah.

Abbas greeted each detainee at his headquarters in Ramallah and told them he would work to win the release of the remaining prisoners.

Abbas' rival, the Islamic extremist group Hamas, has been holding Israeli soldier Gilad Shalit since 2006 and is trying to win freedom for hundreds of Palestinian prisoners as part of a swap.

The expulsion of Falk, a former Princeton University professor, came after he was stopped at Ben-Gurion International Airport after landing Sunday. He was put on a plane yesterday to the United States, said Rupert Colville, a spokesman for the U.N. Office of the High Commissioner for Human Rights.

Yigal Palmor, a spokesman for the Israeli Foreign Ministry, said Falk "comes with his conclusions ready, and those conclusions are of course extreme, methodic criticism of Israel and only of Israel."

Falk could not be reached yesterday for comment.