Gunmen fired on the offices of Palestinian Prime Minister Ismail Haniyeh today only hours after Hamas and Fatah agreed to an Egyptian-brokered truce.
Palestinian gunmen battled inside a hospital and fired on the prime minister's office during factional fighting today that killed 10 people and cast fresh doubt over the future of the unity coalition.
"Everybody is shooting at everybody," a doctor at the Beit Hanoun hospital in the northern Gaza Strip said as a gunbattle raged between the Islamist Hamas and secular Fatah groups, hours after the latest in a series of ceasefires collapsed.
A member of Hamas's Executive Force, two Fatah fighters and another person, who was not immediately identified, were killed and 19 people wounded, hospital officials said.
In separate violence in the northern Gaza town of Beit Lahiya, Jamal Abu al-Jedian, a co-founder of Fatah's al-Aqsa Martyrs Brigades, was killed in a Hamas assault on his house. His home was attacked in revenge for the killing earlier of a Hamas fighter.
"Help us. They want to kill us," a woman inside the house pleaded earlier in a telephone call to a radio station.
The heavy fighting ruined an Egyptian-brokered ceasefire announced just hours before and threw a shadow over long-term prospects for the unity coalition that Hamas and Fatah formed three months ago.
The truce was the latest attempt to end internal strife in which some 620 Palestinians are estimated to have been killed since Hamas beat Fatah in a 2006 election.
The hospital battle, waged inside and outside the facility, was triggered by the shooting of a bodyguard of an intelligence officer affiliated with President Mahmoud Abbas's Fatah faction.
Relatives of the dead man and Fatah fighters then stormed the hospital, which is guarded by the Executive Force, a security contingent loyal to Hamas.
In Gaza City, three Palestinians, including a Fatah gunman and a Hamas fighter, were killed in clashes.
Earlier, gunmen fired on the office of Palestinian Prime Minister Ismail Haniyeh of Hamas. No one was hurt in the attack, which an aide to Mr Haniyeh blamed on Fatah.
But the cabinet session that had been under way in the building was suspended because of the gunfire from a nearby rooftop. Fatah denied its fighters were involved.
Gunmen also stormed a mosque in Gaza City, damaging a library, Hamas said. The incident touched off a gunbattle outside the house of worship. Fatah denied any involvement.
A key motive behind the latest truce was to permit 70,000 high school students in Gaza and the occupied West Bank to take their matriculation exams peacefully.
Most pupils took circuitous routes to their schools to avoid the gunmen, witnesses said.