Hamas security forces opened fire during a mass memorial service for the late Palestinian president Yasser Arafat yesterday, forcing demonstrators to flee in panic during the largest show of force by the rival Fatah movement since Hamas seized control of the Gaza Strip in June.
At least five people were killed and 60 wounded, medical officials said.
Some 250,000 Fatah supporters joined the rally in a major square of Gaza City. As gunshots broke out, protesters scrambled for cover and masked Hamas security men ran through the streets firing weapons.
Bodyguards of senior Fatah officials were seen covering their bosses and dragging them out of the rally grounds.
Two hours later, hundreds of Hamas gunmen were in control of the protest site. Hundreds of protesters were still in the area, trying to get out. Hamas men were seen arresting protesters, and sporadic gunfire could be heard.
An eyewitness, identifying himself as Abu Samir, said Hamas security men appeared to have opened fire unprovoked.
"I saw brutality. I saw gunmen shoot at people. I saw them catch a boy and beat him with a stick," he said.
Hamas officials accused Fatah of provoking the violence.
"Before the rally, Fatah militants were deployed throughout the area," said Ehab Ghussen, spokesman for the Hamas-controlled Interior Ministry. "Fatah is responsible for continued incitement against the Palestinian police, and there was a clear attempt to bring back chaos."
"Whoever thinks that Fatah is dead, let him come and see Gaza today. Gaza is all Fatah," Ahmed Heles, a senior Fatah official, told the rally.
Fatah organizers said Hamas security prevented busloads of Fatah supporters from reaching Gaza City from southern towns.
The violence started when a group of Fatah supporters behind the courtyard came under fire, apparently after throwing stones at the security compound in the area.
Hamas said Fatah gunmen had taken position on the rooftop of a building near the rally site. There were no Fatah gunmen visible on the streets during the clashes, though earlier, a handful of Fatah militiamen were turned away from the rally by event organizers.