JENIN, West Bank — The appearance Saturday of a new Fatah militia raised the stakes in Palestinian President Mahmoud Abbas’ power struggle with the anti-Israel Hamas government, nudging the rivals closer to a large-scale conflict.

More than 2,000 men in black T-shirts and white headbands marched through the West Bank town of Jenin in a signal to Hamas that it has a determined rival in Abbas, who hopes to lead the Palestinians into a peace deal with Israel.

The new unit, which Fatah says has 2,500 members, is the group’s answer to a 3,000-strong Hamas militia that the government mobilized last month over Abbas’ objections. Its presence fueled tensions between Fatah and Hamas that have already brought deadly violence and raised the specter of civil war.

Another 3,000 Fatah activists are training in Gaza in preparation for possible use there, although no decision has so far been taken to deploy them, a Palestinian security official said, speaking on condition of anonymity because he is not authorized to talk to the media.

“It is unacceptable for any faction to field a militia,” Deputy Prime Minister Nasser Shaer of Hamas told a news conference in the West Bank town of Ramallah.

Shaer said the government would resolve the dispute in talks with Fatah.

He said Hamas’ own fighters had been integrated into the official police force, and were therefore not a private army. But Abbas has said he wants the Hamas militiamen off the streets and will not visit the group’s Gaza heartland until they are withdrawn.

Officials in Abbas’ office said Saturday that another reason he will not go to Gaza is because statements from Hamas leaders suggest that 10 days of talks meant to reach agreement on the principle of a Palestinian state alongside Israel will fail.

Abbas has given Hamas, whose leaders are divided over the idea, until early next week to accept the concept of a two-state solution or go to a national referendum on the issue.

The new Fatah force massed in Jenin for a show of force, wearing T-shirts emblazoned with “Special Protection Unit” on the back, and a photo of late Palestinian leader Yasser Arafat on the front. Dozens carried assault rifles or pistols.

Local Fatah leader Ata Abu Rmeileh told them their mission was to reinforce official security branches, which are dominated by Fatah members.

“You are here to protect your people and the Palestinian Authority institutions,” Abu Rmeileh exhorted them over a loudspeaker at the local high school where they gathered. “We are loyal to our people, not like those who have sold themselves to Arab and non-Arab capitals,” he said, in a thinly veiled reference to Hamas, which is supported by Syria and Iran.

Unless Hamas disbands its new force, Fatah will create other militia units across the West Bank and Gaza Strip, Fatah officials said on condition of anonymity because they were not authorized to disclose policy to the media.

Fatah officials say they have information that Hamas wants to flex its muscles beyond its Gaza power base and has begun organizing a militia in the West Bank. Hamas has not confirmed this.

Hamas, ignoring a presidential veto, deployed its paramilitaries in mid-May after Abbas took charge of all the Palestinian security agencies. The Hamas force is overseen by Jamal Abu Samhadana, a key player in rocket attacks on Israel and a suspect in the fatal 2003 bombing of a U.S. convoy in the Gaza Strip.

Fatah deployed its new militia just hours after a senior member of Hamas’ military wing was shot in the chest in a drive-by shooting in Gaza City. Hamas did not blame anyone for the attack on Abdel Hadi Siyam, 35, but officials said Palestinian security personnel fired at him in the same Gaza neighborhood two months ago.

Control of the security forces is key in the power struggle between Abbas, who was elected last year, and Hamas, whose violent ideology has provoked crippling international economic sanctions against the Palestinian government.

The sanctions have kept the new government from paying salaries to 165,000 civil servants over the past three months.

Finance Minister Omar Abdel Razek said the government would pay one month’s salary to 40,000 low-income civil servants on Monday.

Hamas’ accession to government in March has Abbas striving to stave off international isolation. He has given the radical Islamic movement until early next week to accept the idea of a Palestinian state alongside Israel, or go to a national referendum on the issue.

Israeli Prime Minister Ehud Olmert is expected to hold a first meeting with Abbas at the end of June to explore whether resumption of peace talks is viable. On Sunday, Olmert goes to Egypt to meet President Hosni Mubarak in an effort to lay the groundwork for such talks.

In other developments, Israel handed over the bodies of two Egyptian security officers killed in a shootout with Israeli troops on Friday near the Israel-Egyptian border, Israeli and Egyptian officials said. The officers, who crossed the border into Israel, are to be buried on Sunday, an Egyptian security official said.

Essam el-Sheik, the head of Egyptian police in the border area, said it was not clear why the Egyptians had crossed into Israel. Israel said the Egyptians attacked an Israeli military outpost, but Egyptian authorities said Israeli troops fired first.