A rally by Fatah supporters in the Gaza Strip turned deadly Monday when Hamas security forces opened fire on the crowds, killing at least six and injuring about 100.
The rally, attended by an estimated 250,000 Fatah supporters, was held in a major square in Gaza City to mark three years since the death of Palestinian leader Yasser Arafat, who founded the party.
The deaths mark the worst intra-Palestinian fighting since Hamas took control of the Gaza Strip last June after days of bloody violence between the two rival factions.
Fatah supporters, carrying pictures of Arafat and yellow Fatah flags, scattered as masked Hamas gunmen ran through the streets firing weapons.
Two hours later, hundreds of Hamas security men had control of the site and were seen arresting fleeing protesters, reports The Associated Press.
"I saw brutality. I saw gunmen shoot at people. I saw them catch a boy and beat him with a stick,'' a witness, identifying himself as Abu Samir, told the news agency.
Hamas officials accused Fatah of provoking Monday's 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,'' Ghussen said.
Meanwhile, the office of Palestinian President Mahmoud Abbas, who leads the Fatah government, called the shootings a "heinous crime."
Abbas, who resides in the West Bank, had used the anniversary rally to help build support for his party on the streets of Gaza.
Hamas has banned rallies by opposition parties. But a move to prevent a ceremony for Arafat -- who remains well-liked among both factions -- would have been widely unpopular, reports the BBC.
Abbas is preparing for peace talks with Israel later this month in the United States.
Ahead of the negotiations, Israeli Prime Minister Ehud Olmert revealed plans Monday to release more than 400 Palestinian prisoners.
Palestinian officials claim there are about 12,000 Palestinians in Israeli jails. The Israeli human rights group B'Tselem says government statistics place the number at about 8,700.
Since many Palestinian families have relatives in Israeli jails, releases are considered a goodwill gesture meant to build confidence between both sides.
With files from The Associated Press
