The rival Palestinian factions Fatah and Hamas reached a tentative cease-fire Sunday to end days of bloody fighting that had raised tensions in the Gaza Strip to their highest point in a decade, mediators said.

The agreement came after a daylong wave of factional violence that killed three people. Armed militants continued to patrol the streets after the truce was announced, making it uncertain whether it would hold.

Prime Minister Ismail Haniyeh has accused Abbas of inflaming the political crisis by calling for early elections and said his Hamas group would boycott the poll. Abbas, a moderate from Fatah, called for new elections to resolve the political deadlock that has paralyzed the Palestinian government since the hardline Hamas militants won January parliamentary elections.

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Hamas' electoral victory split the Palestinian government, with Abbas seeking peace with Israel and Hamas refusing to even recognize the Jewish state's existence. The political tensions have repeatedly turned violent and the chaos has spiraled out of control since unknown gunmen killed the three young sons of a Fatah-allied security chief last week.

Foreign Minister Mahmoud Zahar's motorcade came under fire Sunday as it drove near the Foreign Ministry in Gaza City. Zahar was unharmed, but the attack unleashed a ferocious gunbattle that raged for more than an hour, the worst fighting since unity government talks broke down late last month. Medical officials said a 19-year-old woman was killed in the crossfire.

Zahar said top Fatah leaders were "fully responsible" for the attack on him "and what will happen."

In a separate attack blamed on Hamas, dozens of gunmen raided a training camp of Abbas' Presidential Guard near the president's residence, killing a member of the elite force.

Hamas gunmen also opened fire at a demonstration of tens of thousands of Fatah supporters in northern Gaza, wounding at least one person, and unknown militants fired at least two mortars at Abbas' office in Gaza City. Hours later, they launched another mortar shell.

Five pro-Fatah security men and a 45-year-old woman were wounded, officials said. Abbas was in the West Bank at the time.

Elsewhere, the bullet-riddled body of a top security officer affiliated with Fatah, Col. Adnan Rahmi, was discovered in northern Gaza several hours after he disappeared, Palestinian medical officials and his family said. No group took responsibility, but Rahmi's family blamed Hamas for the killing.

The violence persisted throughout the night, with Hamas and Fatah gunmen waging battles in the northern Gaza town of Jebaliya, near the home of a Fatah strongman in Gaza, and outside the Gaza parliament building. Hamas militants also clashed with Abbas' bodyguard unit outside his Gaza home.

A French reporter, 46-year-old Didier Francois of the newspaper Liberation, was shot in the leg during the day's violence, according to his newspaper.

Egyptian mediators and small Palestinian factions worked all day to broker an agreement between the two sides, and a truce was announced at a press conference in Gaza City after midnight.

But representatives of Fatah and Hamas did not appear at the press conference, leaving the announcement to Rabbah Muhanna, a senior official in the small Popular Front for the Liberation of Palestine. "Both sides are serious about the agreement," Muhanna assured reporters.

Tawfik Abu Khoussa, a Fatah official, said earlier that his group had agreed to the deal and was working to rein in its forces. Fatah issued a statement calling on its fighters not to fire unless there is a serious threat on their lives. However, the statement also accused Hamas of trying to overthrow Abbas.

"We have intentions about (stopping) the fighting. It is now up to the other side to also stop firing," Khoussa said.

A Hamas official, speaking on condition of anonymity because he was not authorized to talk to the media, said late Sunday the two sides had reached an agreement in principle to halt the violence, but had not finalized the deal.

Despite the violence, the Palestinian president signaled he was determined to push ahead with the plan he announced Saturday to hold new elections. He met with members of the Central Election Commission at his headquarters Sunday to discuss a possible date. The head of the panel said it would take at least three months to prepare new presidential and parliament elections.

"The message of the meeting is that he is serious, that he is saying, 'Don't doubt my words,'" said a top aide, Saeb Erekat. Erekat said he expected elections would be held around June.

Abbas also briefed Secretary of State Condoleezza Rice on the situation Sunday and his efforts to resolve it, said Nabil Abu Rdeneh, an Abbas spokesman.

But Haniyeh rejected the call for new elections.

"We confirm that the Palestinian government refuses the invitation to early elections because it is unconstitutional and could cause tension among Palestinians," Haniyeh said.

Abbas' gamble, after months of indecision, could easily backfire, driving the Palestinians toward all-out civil war or giving Hamas the opportunity to win control of the presidency as well as the parliament and Cabinet that it now controls. But the political deadlock in the Palestinian Authority, and the increasing poverty and violence it has caused, may have left Abbas with little choice.

A poll released Sunday placed Abbas and Haniyeh in a statistical tie in a presidential race. Abbas would win 46 percent, compared with 45 percent for Haniyeh. In parliamentary elections, Fatah would defeat Hamas by a 42-36 margin. The survey was conducted by the independent Palestinian Center for Policy and Survey Research among 1,270 Palestinians and had an error margin of 3 percentage points.

Abbas has suggested he is still leaving the door open to a national unity government with Hamas, which he hoped would end the Palestinian Authority's international isolation, but the growing factional violence made this increasingly unlikely.

In his speech Saturday, Abbas said a unity government was still the best option, but that he had despaired of persuading Hamas to enter into a coalition with Fatah.

The Hamas government has drawn crushing international sanctions over its militantly anti-Israel stand, but has steadfastly refused to recognize Israel as demanded by the West.

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