GAZA CITY, Gaza Strip (AP) – Hamas gunmen shot dead six bodyguards from the rival Fatah movement on Wednesday and mistakenly ambushed a jeep carrying their own fighters, killing five of them, in the bloodiest day of Palestinian infighting since violence erupted in the Gaza Strip four days ago.

Militants from the hardline Islamist group also fired barrages of rockets at Israeli towns, an apparent attempt to draw Israel into the internal Palestinian conflict that has sent the coastal territory spiralling into chaos.

The streets of central Gaza City echoed with the rattle of gunfire, and were empty except for gunmen in black ski masks. Terrified residents huddled in dark homes after electricity to some downtown neighborhoods was cut off by a downed power line.

At mid-day Wednesday, policemen from the Fatah-allied Preventive Security organization arrested five Hamas men and were driving them through Gaza City when the vehicle was ambushed by Hamas fighters, Preventive Security officials told The Associated Press. Five of the Hamas men were killed, along with two Fatah men, they said. The exact circumstances of the incident were not immediately clear.

Hamas radio reported that a Hamas man was killed in another clash, and a nurse traveling in an ambulance was shot in the head after being caught in the crossfire, hospital officials said. Her family said she was brain dead and being kept alive by a respirator.

In four days of fighting, 41 people have been killed and dozens more have been injured. The majority of the fatalities have been from Fatah.

Fighting raged close to Palestinian President Mahmoud Abbas’s heavily guarded compound Wednesday morning, which was also targeted by Hamas mortar fire overnight, and the bodies of two Fatah gunmen could be seen sprawled on the street nearby. Abbas, a moderate from Fatah, was not present.

Early Wednesday, Hamas gunmen fired mortars and pipe bombs at the home of Fatah security chief Rashid Abu Shbak, before storming inside and killing six bodyguards, Palestinians security and medical officials said.

Abu Shbak and his family were not home at the time of the attack, but the house was guarded by at least a dozen of his bodyguards. Dozens of reinforcements from the Preventive Security organization, which Abu Shbak used to head, were sent in to join the fighting.

Abdel Hakim Awad, a Fatah spokesman, angrily accused Hamas’ leadership of the attack on Abu Shbak’s house. “All (Hamas) are killers from top to bottom, all are implicated,” he said, charging that the Islamist group “wanted to turn Gaza into a new Somalia or Darfur.”

Hamas officials said the organization’s men launched eight rockets at Israel on Wednesday, following a barrage of around 20 rockets a day earlier. That salvo at the Israeli town of Sderot, just outside Gaza, wounded 21 Israelis, one seriously, a woman whose house took a direct hit, said Yerucham Mendola, spokesman for the Red Star of David, the Israeli equivalent of the Red Cross. There were no casualties Wednesday morning, but school was canceled in Sderot and residents huddled in bomb shelters.

Hamas said its rockets were retaliation for Israeli violence, but more likely it was an attempt to draw Israel into the fighting as a way of uniting the Palestinians against a common foe.

Wednesday’s violence in Gaza followed a stunning Hamas attack the previous day on a group of Fatah-affiliated policemen at the coastal strip’s only cargo crossing, a strategic installation where U.S. Experts have been involved in planning security. In that attack, Hamas gunmen surrounded a Fatah police jeep and riddled its passengers with bullets at close range, killing eight.

Israeli Defense Minister Amir Peretz summoned army commanders for late-night consultations to consider Israel’s next move. Israeli security officials said there would be no large-scale military response to the rocket fire so as not to play into Hamas’s hands.

“Israel is not going to be dragged into the Gaza Strip the way that Hamas wants. We will choose the time, the place to respond and we will protect our citizens,” said Israeli government spokeswoman Miri Eisin.

Israel was briefly drawn into the internal Palestinian violence during the border crossing attack Tuesday, when Israeli troops shot and killed a Fatah man who approached the border fence during the Hamas attack.

On Wednesday morning, Israeli aircraft fired at open areas in northern Gaza in an attempt to deter Palestinian rocket squads, a military spokesman said.

An Egyptian mediator said a truce was reached late Tuesday, the third in as many nights. But like the previous ones, Tuesday’s agreement collapsed within hours.

On Hamas’ radio frequency, the organization’s fighters could be heard referring to their Fatah rivals as “American mercenaries,” a reference to the Western support enjoyed by Fatah.

Gaza’s turmoil further weakened hopes for a resumption of Israeli-Palestinian peace talks, despite a new push by the Arab world to bring the sides to the table. The offer proposes Arab recognition of Israel in exchange for an Israeli withdrawal from all lands it occupied in the 1967 Mideast War.

Negotiations, however, are inconceivable if the Palestinians descend into civil war.

Still, Israeli Prime Minister Ehud Olmert and King Abdullah ll of Jordan met Tuesday at the king’s seaside palace in Aqaba in the highest-level attempt yet to push forward the Arab initiative.

This week’s fighting was the worst since Hamas and Fatah agreed in February to share power.

At the core of the fighting is the unresolved power struggle between Hamas, which won parliament elections last year, and Abbas’ Fatah, which dominated Palestinian politics for four decades. After a year in power and squeezed by an international aid boycott, Hamas realized it could not govern alone and brought Fatah into the government. But the two sides never worked out all their differences, particularly over who would control the Palestinian security forces. On Wednesday, a group of Fatah lawmakers called on Abbas to use his constitutional powers to declare a state of emergency and dismiss the Hamas-led unity government, replacing it with his appointees. But such a step would almost certainly be rejected by Hamas and draw more violence.