Gaza's Hamas government said Monday it was searching for three suspects in last week's killing of an Italian activist.
Hamas has been conducting a manhunt since the death of Vittorio Arrigoni, an Italian activist who had been assisting local Palestinians in Gaza.
The 36-year-old's body was found early Friday, hours after a video showing him beaten and blindfolded surfaced on the Internet.
It was the first kidnapping of a foreigner in Gaza since Hamas seized control of the territory in 2007. It highlighted the challenge that Hamas, an Iranian-backed group that promotes armed struggled against Israel, faces from smaller, extremist factions that consider it too pragmatic.
Hamas' police posted pictures of the suspects on its official website on Monday. Officials said the men, who included a former Hamas policeman and a Jordanian activist, belong to a small extremist Islamic group inspired by al-Qaida.
In the video of Arrigoni, a group identifying itself as "Monotheism and Holy War" demanded the release of two of its leaders, held by Hamas, in exchange for the hostage.
Hamas said Arrigoni was strangled, but it has not allowed an independent expert to see the body.
After a symbolic military funeral, Palestinian policemen carried Arrigoni's coffin, decorated with Palestinian and Italian flags, to a waiting ambulance as young activists threw flowers on it. With police cars escorting the ambulance, the body was taken Monday to neighboring Egypt, from where it was later to be transferred to Italy for burial.
In Gaza, the shadowy radical groups that rival Hamas are part of the "Salafi" movement, which preaches ultraconservative Islam that strictly segregates the sexes and vehemently rejects anything but a strict, hard-line interpretation of Islamic law.
Some, including the group apparently behind Arrigoni's abduction, are inspired by al-Qaida and call for actively waging jihad, or holy war, against those perceived as Islam's enemies. Hamas denies claims that al-Qaida is active in Gaza.
Police identified the suspects in Arrigoni's slaying as Bilal al-Umari, Mahmoud al-Salfiti, a former Hamas policeman, and Abdel Rahman Brezat, a Jordanian who is believed to have sneaked into Gaza last year. Authorities said all three men were believed to still be in the coastal territory.
Arrigoni was an activist with the International Solidarity Movement, a pro-Palestinian group that often sends activists to prevent the Israeli military from carrying out missions in the West Bank and Gaza. The group said Arrigoni had been working with Palestinian farmers and fishermen.
ISM says it is committed to nonviolent means of protest, but its activists often enter dangerous situations.
Rachel Corrie, 23, of Olympia, Washington, was crushed to death by an Israeli army bulldozer while trying to block it from demolishing a home in Gaza. A British activist was killed by an Israeli soldier in Gaza in 2003. A Palestinian ISM activist was killed by a Palestinian militant in the West Bank town of Jenin in 2007.