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Palestinian presidential candidate Mahmoud Abbas (search) rode on the shoulders of the West Bank's most famous gunman during a campaign stop, prompting questions of whether Abbas is playing campaign politics or identifying with violent groups.

Zakaria Zubeidi, the local leader of the Al Aqsa Martyrs' Brigades (search), a violent group with ties to Abbas' ruling Fatah party (search), took center stage when Abbas came to visit the battered Jenin refugee camp on Thursday. Assault rifle slung over his shoulder, Zubeidi and other gunmen hoisted Abbas onto their shoulders, and the candidate smiled and waved.

Meanwhile, Israeli forces expanded a sweep through the Khan Younis refugee camp in southern Gaza, where militants fire mortars and rockets at nearby Jewish settlements. After nightfall, four gunmen were killed in an Israeli air strike, witnesses and Palestinian security said. The military said the air force fired at four gunmen and hit them.

Five Palestinians — three gunmen and two civilians — were killed in earlier clashes on Thursday.

Israel has been quietly backing Abbas, considering him a moderate who has called attacks against Israelis a mistake. Israelis contrast him with Yasser Arafat, whom they shunned, charging he was involved in terrorism.

However, with the election less than two weeks away, and Abbas constantly referring to Arafat as his guide and associating with militants like Zubeidi, some Israelis are having second thoughts.

Zubeidi is idolized in the camp for his swagger and wanted by Israel for organizing attacks and sending suicide bombers into Israeli cities. Jenin was the scene of heavy fighting during an Israeli incursion in 2002 that followed one of the bombings.

Abbas won Zubeidi's ringing endorsement. After Abbas left the stage, Zubeidi, with gunmen firing in the air, warned that he would deal with anyone who tried to challenge the elected Palestinian leadership. Then Zubeidi escorted Abbas' car out of the camp.

Palestinian analysts say Abbas needs to win the election in a landslide to capture even part of the emotional backing Yasser Arafat had, possibly explaining his trip to the camp and embrace of Zubeidi.

In his address, Abbas referred to the 2002 battle, in which 52 Palestinians and 23 Israeli soldiers were killed, recalling that Yasser Arafat called the camp "Jeningrad." The crowd responded with a healthy cheer.

"When we demand security," Abbas said, "we demand it for all our citizens, including our wanted brothers who also deserve a life of security and safety," he said, in a reference to Zubeidi and his group, evoking another big cheer.

Abbas also pressed other themes — restoring the rule of law and negotiating a peace deal with Israel.

Officials in Sharon's office refused to comment, but the chairman of the influential parliamentary Foreign Affairs and Defense Committee, Yuval Steinitz, counseled caution about seeing Abbas as a ticket to a quick peace agreement.

"The meeting with Zakaria Zubeidi, an accomplished and proud terrorist, is one more cause for worry," Steinitz said. Disillusioned by failure of the interim peace accords Israel and the Palestinians signed in the 1990s, Steinitz added, "we have learned that we cannot take such worrying signals lightly."

However, Palestinians close to Abbas say the visit to Jenin and the pro-Arafat rhetoric are just campaign moves. Abbas, 69, Arafat's longtime deputy, lacks Arafat's charisma and appeal and has the image of a soft bureaucrat — a perception he needs to toughen in order to win support from young Palestinians caught up in the struggle against Israel.

Aide Ahmed Subah said Abbas "has a program and he's explaining his program to his audience," varying the message accordingly. The "real Abu Mazen," Abbas' nickname, is intent on "ending the Israeli occupation through peaceful negotiations, attaining security for Palestinian citizens and achieving reform and development," Subah said.

Israeli analyst Dan Scheuftan warned that Abbas' embracing of Zubeidi might backfire, whatever his intentions.

"If he believes that by associating with Zubeidi, he gets control of him," Scheuftan said, "this is not the case."

After nightfall Thursday, Israeli troops arrested Zubeidi's brother Jibril, 23, along with three other Palestinians. Military officials said he was carrying an assault rifle when he surrendered.