Hamas supporters stormed a crowd of protestors in the Gaza Strip who had gathered on Tuesday to demand Palestinian unity, witnesses said.
Tens of thousands of Palestinians had initially answered a rallying call on Facebook demonstrate in Gaza and the West Bank for reconciliation between Hamas Islamists and President Mahmoud Abbas's rival Fatah group.
A couple of thousand demonstrators remained on the streets of Gaza as the protest wound down, defying calls by Hamas, who controls the territory, to disperse. It was the first time Hamas' authority was challenged in such a public manner since it seized control of Gaza from Fatah in 2007.
"They attacked us, 400 to 500 Hamas men in plain clothes. I was beaten with a club, many others were beaten," said one activist, who gave only his first name Ali. "They dispersed the crowd."
There was no word on how many were hurt in the clash.
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