The U.S. government wants to determine what role, if any, one of 13 Palestinian militants freed from the Church of the Nativity might have played in the shooting death of a Brooklyn-born architect this year in Israel.

Israel has blamed the Jan. 15 slaying of Avi Boaz, 71, on Ibrahim Moussa Salem Abayat, 29, a leader in the Al Aqsa Brigades, the militia that claimed responsibility for Boaz's death.

There are no criminal charges filed in the United States in Boaz's death, but authorities here want to determine whether Abayat was involved, a U.S. official said, speaking on condition of anonymity.

Because of the complicated international negotiations surrounding the 13 Palestinians, however, it was unclear what the United States could do even if it were to determine that Abayat was involved, the official said.

The 13 militants, described by Israel as senior terrorists, met Monday with Arab diplomats in Cyprus, where they arrived Friday as a transit point following the end of the 39-day standoff at the church in Bethlehem.

The European Union said Monday that six nations — Belgium, Greece, Ireland, Italy, Portugal and Spain — were ready to take the Palestinians as a gesture to defuse tensions in the Middle East. The EU said the 13 won't be arrested or detained.

The 13 were taken from the Church of the Nativity to Cyprus on Friday under a deal backed by the EU, the United States and the Vatican. Twenty-six other Palestinian militants were sent to the Gaza Strip.

Boaz, who moved to Israel in 1961 from Manhattan, was killed as he was looking for materials for a house he was building in the Jewish settlement of Har Gilo in the West Bank. He frequently used his American passport to get past Israeli military checkpoints around Palestinian towns, and his family said he always believed his American citizenship would protect him.

But four civilian gunmen carjacked his silver Rover sport-utility vehicle, drove him to a soccer field in nearby Beit Sahour, exited the car and fired 20 times into the windshield. Boaz, who never accepted Israeli citizenship, is buried in Jerusalem.

The Al Aqsa Brigades said after the attack that Boaz's death was in retaliation for the bombing death of a local militia leader blamed on Israeli forces.

Boaz's closest friend was a Palestinian hotel owner in the West Bank whose own brother was a hijacker killed by Israel in the 1976 Entebbe rescue operation. Boaz and Jamal al-Arja remained close through decades of the Israeli-Palestinian conflict, sharing meals, vacationing together and attending the weddings of each others' children. Al-Arja's son, Bashir, was in Boaz's vehicle when Palestinian gunmen stopped it at a police checkpoint and threw the boy from the car before driving off and killing Boaz.