JERUSALEM -- Fighters from the Islamic group Hamas overran a key base and other positions of rival Fatah security forces in the Gaza Strip yesterday, pressing a broad assault that supporters of Palestinian Authority President Mahmoud Abbas called an attempted coup to seize the government.
The Hamas advances signaled a possible turning point in the power struggle between the factions that has taken hundreds of lives since Hamas won parliamentary elections in 2006, defeating Abbas' Fatah party.
The fighting has escalated into what many in Gaza are calling a civil war. It has included execution-style killings, shootouts at hospitals and instances in which handcuffed prisoners were hurled to their deaths from apartment towers.
At least 28 Palestinians were killed yesterday, hospital officials said. More than 40 have died in clashes this week.
The internal strife has dimmed prospects for a revival of regional peace efforts, undercutting attempts to restart talks between Palestinians and Israelis. The United States has aided Abbas, who favors negotiations, while Hamas rejects any permanent peace with Israel.
In what was seen as a key gain, Hamas forces captured the headquarters of the Fatah-led National Security Force in the northern Gaza Strip yesterday after a battle that claimed at least 13 lives. The compound near the Jabaliya refugee camp was pounded with mortars, rocket-propelled grenades and machine guns.
Other Fatah posts were taken by Hamas fighters, and residents said the militant group was in control of the northern and central Gaza Strip, with Fatah still controlling key security installations in Gaza City, including the presidential compound.
Fatah's Central Committee warned after a meeting led by Abbas at his West Bank headquarters in Ramallah that Fatah ministers would suspend participation in a unity government with Hamas if the fighting does not stop. The shaky coalition was formed three months ago.
The leader of an Egyptian mediation team in Gaza, Lt. Gen. Burhan Hamad, said there was "no one to talk to" in the warring factions, and he called on ordinary Palestinians to take to the streets today to demand an end to the bloodshed.
Several incidents raised fears that the factional violence could spread to the West Bank. A deputy Cabinet minister from Hamas was kidnapped by Fatah gunmen and Abbas' presidential guards raided offices of a Hamas-controlled television station, confiscating equipment and arresting three staff members.
Late yesterday, Fatah gunmen wounded four Hamas members in the West Bank city of Nablus, according to a Fatah statement reported by the Associated Press.
Fighting raged across Gaza City yesterday as residents huddled in their homes and combatants targeted symbols of leadership. A rocket-propelled grenade hit the house of Prime Minister Ismail Haniyeh of Hamas in the Shati refugee camp, but there were no casualties. Mortar shells landed near Abbas' residence in Gaza. Neither leader was home.
Hamas fighters warned Fatah security forces to evacuate their bases, then attacked security compounds and positions in what appeared to be an assault on several fronts.
Fatah commanders complained that they were not given clear orders to respond and that they had no central command. Fatah's strongman in Gaza, Mohammed Dahlan, has been in Egypt for several weeks, reportedly recovering from knee surgery.
The United States has worked to bolster Abbas' presidential guard with training, and Israel has allowed his forces to bring in arms and reinforcements through Egypt. But they appeared outgunned and overwhelmed by better-organized Hamas fighters, drawn from the group's armed wing and security force.
In Gaza City, gunfire and explosions were heard from a base of Abbas' paramilitary National Security Force, whose commanders issued an order exhorting troops to "confront the seekers of the coup." The order described Hamas as a "bloody party which is launching a coup against the president and against the authority and national unity government."
Hamas called the attack on Haniyeh's home an assassination attempt. "They have crossed all the red lines," said Hamas spokesman Fawzi Barhoum.
Fighting erupted near the headquarters of the Fatah-led Preventive Security Service, with Hamas fighters firing mortars and drawing return fire. Fatah forces tried to attack Hamas' main television station but were repelled and their vehicles burned.
In Khan Yunis, in the central Gaza Strip, Hamas fighters captured the district government building and exchanged fire with Fatah forces at the security headquarters.
Nabil Shaath, a prominent Abbas aide and former foreign minister, said his house in Gaza had been raided and burned, though his family was not there. The home of Samih al-Madhoun, a leader of the Aqsa Martyrs Brigades, the armed wing of Fatah, was burned, and Hamas gunmen also attacked the home of Fatah spokesman Maher Mikdad.
Israeli Prime Minister Ehud Olmert said that "serious consideration" should be given to posting international forces along the Gaza Strip's border with Egypt to keep arms from reaching Palestinian militants.
"If the Gaza Strip ultimately falls to Hamas, this will be of great regional significance," said Olmert, who added that Israeli forces would not enter Gaza to help Abbas.
Joel Greenberg writes for the Chicago Tribune.