At least 11 people are reported killed and scores injured in an alleged attack on protesters in the Egyptian capital of Cairo.
The Associated Press quoted security officials as saying that the attack was carried out at dawn on Wednesday by unidentified, plain-clothed assailants.
They targeted several hundred protesters who had been camping out by the Ministry of Defense in Cairo's Abbasiya district for several days.
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According to Reuters, many of the demonstrators were supporters of a Salafist preacher disqualified by electoral authorities from the presidential election later this month, while others were calling for an end to military rule.
More than 160 people were injured in the clashes, security and medical sources told the news agency.
Witnesses described seeing homemade bombs, stones, Molotov cocktails, teargas and shotguns loaded with birdshot used against protesters, Egyptian news site Ahram Online reported.
The violence continued for several hours after the initial attack, according to the BBC, which said that some demonstrators retaliated against their assailants.
Soldiers and police intervened to stop the clashes, but only several hours after they began.
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Some accused the ruling military council of acting too late, or even of organizing the attacks. Nobel laureate Mohammed El Baradei tweeted:
A number of presidential candidates have suspended their campaigns in protest at the authorities' response, Ahram said, including Mohammed Mursi of the Muslim Brotherhood's Freedom and Justice Party and independents Abdel-Moneim Abul-Fotouh and Khaled Ali.
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