A new power struggle has erupted between Palestinian Authority Prime Minister Mahmoud Abbas and President Yasser Arafat -- this time over control of the huge and unwieldy Palestinian security apparatus, whose loyalties are divided between the two men.
The timing of this duel is particularly critical, coming as Abbas is struggling to prove to Israel that he is capable of taking substantive steps to prevent terror attacks like the grisly bus bombing in Jerusalem last week that killed 21 people and shattered two months of relative calm. The Islamic militant group Hamas claimed responsibility for the attack.
Late Sunday, pressing ahead with a campaign of retaliation against the group, Israeli forces killed four members of Hamas' military wing in a missile strike on the southern outskirts of Gaza City. Palestinian witnesses said an Israeli attack helicopter pursued the men after they jumped from their car and tried to flee into an open field.
Palestinian sources described the four men as field operatives, not senior leaders. But Israel said one of the slain men, Ahmed Ishtawi, was a top fugitive who had recently taken a prominent role in organizing attacks by the Hamas military wing, Izzidin al-Qassam.
The dispute between Abbas and Arafat reignites a long-running struggle between the two, which intensified after Israel and the Palestinians formally endorsed the U.S.-backed peace initiative known as the "road map" at a June 4 summit presided over by President Bush.
The Palestinians have nearly 60,000 men under arms, by most estimates, and about two-thirds of them are believed to answer to Arafat and his allies, rather than the beleaguered team of Abbas and his security chief, Mohammed Dahlan, which the Bush administration supports.
Since his appointment to the premiership in April, Abbas, also known as Abu Mazen, has been hobbled by a lack of control over the security forces, which are divided into multiple branches of police, paramilitary forces, intelligence and preventive security.
Many analysts believe that lack of muscle was a factor in Abbas' decision to try to negotiate with militant groups such as Hamas and Islamic Jihad rather than going after their leaders and arms caches. Abbas has said he believes an all-out confrontation with the militant groups would be tantamount to civil war.
"Abu Mazen lacks the basic, preliminary tool, which is a united force," said Shalom Harari, a former official in Israel's Shin Bet domestic intelligence service. "In practice, Abu Mazen is in control of only about 20,000 men -- Arafat is in control of all the rest."
The latest maneuvering by Arafat's camp began Saturday night, when the policymaking Central Committee of Arafat's Fatah faction called for the naming of Nasser Yousef, an Arafat loyalist, as interior minister, a job Abbas has left unfilled.
That was widely interpreted as an effort to sideline Dahlan, who would have been forced to report to Yousef -- a comrade-in-arms of Arafat during the Palestine Liberation Organization's years of exile in Lebanon and Tunisia in the 1980s and early 1990s.
By Sunday, the appointment appeared in doubt. However, Palestinian officials speaking on condition of anonymity suggested that the reversal did not signal a victory for Abbas and Dahlan but rather came about because Arafat had qualms about handing over so much power to Yousef.
Publicly, Palestinians sought to play down the internal feud, even though Israeli media reports said the dispute had grown so heated that Abbas and Dahlan had threatened to quit. The Palestinian minister of information, Nabil Amr, told Israel's Army Radio, "We simply want to unify our security forces under one umbrella."
Abbas' government had balked last week at imposing a crackdown on the militant groups after Israel assassinated a top Hamas leader, Ismail abu Shanab, in retaliation for Tuesday's bombing.
But in a change of course, Dahlan's forces moved Saturday night and Sunday to block the entrances of four tunnels running under the Egyptian border, which had been used to smuggle weaponry into the Gaza Strip, and arrested several smugglers.
Israel, though, derided the step as an insignificant and probably temporary measure.
"The Palestinian operations look more like they're directed for public relations rather than toward permanently closing the tunnels," said Israeli government spokesman Dore Gold. "Israel would have hoped that the Palestinians would have blown up the tunnels, rather than shovel sand into the entrances in front of the cameras."
For months now, Arafat has been viewed by both Israel and the United States as an obstacle to a crackdown on the militant groups. But there were signs he might be seeking to rehabilitate himself in the eyes of the Bush administration and the government of Ariel Sharon.
On Sunday evening, Arafat's security chief in Gaza, Maj. Gen. Abdel Razek Majaydeh, ordered his forces to take steps to halt rocket and mortar attacks against Israeli targets, Palestinian security sources said.
That move came hours after Palestinian militants succeeded in firing a new, longer-range rocket into Israel -- rattling the country, even though the projectile caused no injuries or damage. It landed about four miles south of the Israeli city of Ashkelon, 15 miles north of the Gaza Strip, which has been well out of range of the Palestinians' homemade Kassam rockets.
Elsewhere, Israeli troops operated inside the northern West Bank city of Nablus for the fourth straight day, searching for wanted Palestinian militants and stores of weapons. The army said troops had discovered and destroyed an explosives laboratory in the heart of the city.