Thousands of Palestinians throughout Gaza and the West Bank turned out Tuesday to protest the deaths of three children in a drive-by shooting, and Hamas gunmen — blamed by many for the killings — opened fire on demonstrators from the rival Fatah movement.

The killings of the three boys — ages 3, 6 and 9 — whose car was riddled with bullets as they rode to school in Gaza City, sparked widespread rage, grief and soul-searching in the Palestinian areas. Children stayed home from school and stores were closed to protest the violence.

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While Gaza has been plagued by months of infighting, the brutality of Monday's shooting — in an area crowded with families and schoolchildren — was especially shocking and raised fears of more factional violence. Women led many of Tuesday's protests, demanding safety for their children.

"This is something we have never experienced here. We are asking ourselves: Are we close to civil war?" asked Mayson Muzien, 27, who joined dozens of women at a mourning tent outside the residence of President Mahmoud Abbas in Gaza City. Many protesters carried posters with life-size photos of the dead boys' bloodied faces, as well as other victims of Palestinian infighting.

Monday's drive-by shooting immediately raised fears of renewed fighting between Fatah and Hamas, which have been locked in a power struggle since Hamas won parliamentary elections in January.

Fatah officials accused Hamas of carrying out Monday's attack.

The children's father, Baha Balousheh, is an intelligence officer and Fatah loyalist who helped lead a crackdown on Hamas a decade ago. Balousheh, who was not in the car, had escaped two previous assassination attempts. The Islamic group denied involvement and condemned the killing.

The shooting Tuesday's left four people wounded at a protest led by Fatah in the southern Gaza town of Khan Younis.

Saleh Hammad, a local Fatah leader, said the demonstration was peaceful, although he acknowledged that some children threw stones. "Even if one or a few children lost their temper and stoned the members of the unit, this is not a reason to be fired at," he said.

Islam Shawan, a Hamas spokesman, said the militiamen did not fire at the crowd. "Our personnel were attacked by shooting and stones," he said.

But hospital officials confirmed four people were wounded, one moderately. The demonstration quickly dispersed, and there were no further signs of fighting.

Abbas, a political moderate, ordered security forces loyal to his Fatah party to take up positions on main roads and at major intersections throughout Gaza City in an effort to maintain order. In many places, Hamas militiamen patrolled nearby. While the atmosphere was tense, there were no reports of violence.

In Gaza City, schools were forced to cancel classes after children refused to go to class. In some cases, students burned tires, blocked roads or held small demonstrations outside the buildings.

Grieving women called into local radio stations, while newspaper editorials criticized Palestinian leaders for allowing security to deteriorate.

"Are we the brave heroes or are we the terrorists the media speaks of," sobbed one woman who called a Gaza radio station.

Meanwhile, demonstrations took place in all major West Bank cities. Some 1,500 people thronged downtown Nablus, and in Jenin, about 300 children staged a march.

In Hebron, about 1,000 marched through the city, with gunmen firing in the air. Participants called for the resignation of the Hamas-led government.

Months of tensions between Fatah and Hamas have heightened since Abbas' efforts to form a unity government with the Islamic group broke down last month. Earlier this week, Abbas threatened to call early elections to end the standoff, drawing Hamas accusations that he is plotting a coup.

Abbas is expected to deliver a major policy speech on Saturday to discuss his plan for early elections, aides said Tuesday. However, Abbas will not give a date to give the unity talks more time, they said.

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