Four Palestinians died and dozens were wounded in street battles on Saturday between forces of Hamas and Fatah movements in Gaza City, prompting Israel to go on the alert.
The clashes was sparked in the morning when Hamas security forces tried to arrest suspects thought to be behind a July 25 bombing that killed five Hamas members and a little girl on a Gaza beach.
Hamas said two of its men were killed and Palestinian medical officials reported two more dead and scores of wounded in Saturday's firefights. According to AFP, Israeli authorities and health services in areas skirting the Gaza Strip went on increased alert amid fears that the violence would spill over into Israel.
"A member of the Hamas police and a member of the Ezzedine al-Qassam Brigades (the military wing of Hamas) were martyred" in the clashes, Hamas said in a statement.
Gaza emergency services official said that two other Palestinians died and more than 60 people were hurt in the fighting, including seven in serious condition.
The clashes broke out around a house belonging to the influential pro-Fatah Hilis clan in the Shujwa neighbourhood of Gaza.
Hamas spokesman Sami Abu Zuhri charged that members of Hilis family and other unidentified associates had "fired mortar rounds at the Hamas police as well as a rocket at Gaza City" from inside the Shujwa house. Several members of the Hilis clan "are responsible" for the deadly July 25 bomb attack and Hamas is determined to round up the suspects, Abu Zuhri told AFP.
"There have been several arrests and there will be many more. We have asked the police to be firm," he said.
But Adel Hilis, a Fatah leader, denied that clan members opened fire on Hamas.
"These are lies. We never fired rockets or mortar rounds. Hamas is the one committing crimes. We have asked all the Palestinian factions, Islamists and nationalists, to use their influence so that these crimes cease," he said.
