Syrian authorities have arrested one of the associates of assassinated Hamas member Mahmoud al-Mabhouh for possible involvement in the plot, a Fatah-affiliated website reported Tuesday.

The man, Mahmoud Nasser, was said to have been aware of all of Mabhouh's movements and flights. According to an Arab diplomatic source, the Dubai police asked the Syrians to turn over Hamas members for questioning, including Nasser.

Nasser arrived in Dubai shortly before the assassination, and the Syrians suspect he cooperated with the assassins and provided information on Mabhouh's whereabouts. According to the reports, Nasser was one of those who rook part in the kidnapping and killing of Israel Defense Forces soldiers Avi Sasportas and Ilan Saadon during the first intifada, together with Mabhouh.

Meanwhile, the Dubai police have uncovered the identity of four additional people involved in the assassination operation. Sources in the United Arab Emirates told the al-Jazeera network that two of the people used British passports and the other two used Irish passports.

The al-Hurra network quoted "senior Jerusalem sources" as saying that "there is a strong cooperation between Israel, France, Britain, Jordan and Egypt in fighting the Hamas terror."

One of the same sources told the network that "the relations between the Israeli Mossad and the Egyptian and Jordanian security organizations will not be harmed following the Mabhouh assassination, especially in light of the fact that the two countries view Hamas as part of the Muslim Brotherhood movement which seeks to bring down Mubarak's regime in Egypt and King Abdullah's regime in Jordan."