As Fatah's last security command centers fell after four days of fighting, Hamas military men in black masks moved unchallenged across Gaza City, hunting down foes, blowing up homes and dragging the body of a top Fatah militant through the streets.
Hamas fighters marched humiliated agents of the once-feared Preventive Security Service out of their headquarters in handcuffs and stripped to the waist. The Islamic movement finished its rout by taking the Presidential Guard headquarters without a fight as its defenders fled by boat toward Egypt.
In the West Bank, Palestinian Authority President Mahmoud Abbas, the Fatah leader, reacted to the defeat by firing the Hamas-led Cabinet and declaring a state of emergency. He said he would name an interim government and hinted at new elections.
The president's decrees, largely unenforceable in Gaza, appear certain to solidify the divide between his secular Fatah party, which favors negotiations with Israel, and its Gaza-based Islamic rival, which is backed by Syria and Iran and advocates the destruction of the Jewish state.
But Abbas' move could thwart Hamas' efforts to gain international recognition and aid from the West, which has demanded that Hamas recognize Israel, renounce violence and accept all previous accords between the Jewish state and the Palestinians.
"Abbas is telling the world that the current government does not represent the Palestinian Authority and therefore the world should not deal with it," said Azmi Shueibi, a former Palestinian legislator.
At a Gaza City news conference early today, Prime Minister Ismail Haniyeh of Hamas called Abbas' decrees "hasty" and declared that he would remain in his post. He said the Hamas militia would impose law and order in Gaza "firmly, decisively and legally."
The two factions had fought sporadically since Hamas unseated Fatah in parliamentary elections in January 2006, but not with the ferocity seen this week. Hamas reluctantly brought Fatah into the Cabinet in March to quell earlier violence and ease its diplomatic isolation, but the uneasy alliance began unraveling last month with feuding over control of security agencies employing tens of thousands of men.
Firing mortars, rocket-propelled grenades and automatic weapons, Hamas fighters captured the Gaza City headquarters of the Preventative Security, intelligence and National Security agencies yesterday afternoon, and executed some of their captives. The Presidential Guard compound fell late in the evening. All had been controlled by Fatah.
Earlier in the day, Hamas had overrun the main Fatah compound in the southern city of Rafah, giving it full control of the border with Egypt, a source of the smuggled weapons that have expanded the Islamic movement's arsenal in recent months.
At least 33 people were killed yesterday in Gaza, pushing the four-day death toll over 90.
The intensity of the fighting prompted the European Union to suspend its humanitarian relief projects in the impoverished seaside territory. The United Nations already had curtailed its food distribution program, which serves one-third of Gaza's 1.4 million residents, after two of its aid workers died in the crossfire.
Yesterday's fiercest battle raged at the Preventive Security headquarters, a target especially despised by Hamas militants because of the agency's bloody crackdowns on the movement a decade ago.
Hamas fighters overran the headquarters in a hail of fire. They raised green Islamic flags over the shattered two-story compound, kissed the ground in prayer and marched handcuffed Fatah gunmen into the streets.
"There is a history to it, a vendetta and a settling of scores," said Palestinian lawmaker Hanan Ashrawi.
Fatah officials said Hamas gunmen shot seven captured Fatah fighters outside the Preventive Security compound. Witnesses confirmed two executions.
The rout of Fatah was swift, owing to Hamas' superior discipline against a disorganized, dispirited foe that ran short of arms and ammunition.
Fatah's Al Aqsa Martyrs Brigades retaliated with attacks on Hamas loyalists in the West Bank. Hamas said one member was killed and 23 others abducted in West Bank cities, some within sight of police. In Nablus, Fatah gunmen stormed a Hamas office, hurled computers from the windows and set it ablaze.
In Washington, Secretary of State Condoleezza Rice said the United States backed Abbas' decrees. Abbas had informed Rice of his decision in a phone call.
"President Abbas has exercised his lawful authority as president of the Palestinian Authority, as leader of the Palestinian people," Rice said. "We fully support him in his decision to try and end this crisis for the Palestinian people and give them an opportunity to return to peace and a better future."
Rushdi abu Alouf and Richard Boudreaux write for the Los Angeles Times.