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An American citizen was killed in Alexandria, Egypt, the scene of violent clashes between supporters and opponents of President Mohammed Morsi, the State Department confirmed to Fox News Friday.

Andrew Pochter, 21, a student at Kenyon College in Gambier, Ohio, was one of three people killed Friday in clashes between competing camps trying to show their strength before even bigger nationwide protests planned by the opposition Sunday.

Pochter was in Egypt as an intern with AMIDEAST, an American nonprofit engaged in education, training and development activities in the region, according to a statement released by Kenyon College early Saturday.

A medical official told The Associated Press that he died of gunshot wounds at a hospital. The official spoke on condition of anonymity because he was not authorized to speak to the press.

The Alexandria health department reported an Egyptian also died from a gunshot wound to the head. It was not immediately known if that victim was a Morsi opponent or supporter.

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    Earlier Friday, the Obama administration warned Americans against all but essential travel to Egypt, where further demonstrations are planned this weekend.

    It also said it would allow some nonessential staff and the families of personnel at the U.S. embassy in Cairo to leave Egypt until conditions improve.

    "Political unrest, which intensified prior to the constitutional referendum in December 2012 and the anniversary in 2013 of Egypt's 25th January Revolution, is likely to continue in the near future due to unrest focused on the first anniversary of the president's assumption of office," the State Department said in an earlier statement.

    "Participants have thrown rocks and Molotov cocktails and security forces have used tear gas and other crowd control measures against demonstrators. There are numerous reports of the use of firearms as well," it added.

    The department also said it had authorized the departure of "a limited number of non-emergency personnel" in addition to family members.

    That move doesn't require anyone to depart but encourages them to go by allowing them to do so at government expense. Officials said dependents and nonessential staff could be ordered to leave if the situation deteriorates.

    The Cairo International Airport was flooded with departing passengers, an exodus that officials said was unprecedented. All flights departing Friday to Europe, the U.S. and the Gulf were fully booked, they said.

    Many of those leaving were families of Egyptian officials and businessmen and those of foreign and Arab League diplomats — as well as many Egyptian Christians, the officials said, speaking on condition of anonymity because they were not authorized to talk to the press.

    In Alexandria, on the Mediterranean coast, fighting began when thousands of anti-Morsi demonstrators marched toward the Brotherhood's headquarters, where up to 1,000 supporters of the president were deployed, protecting the building.

    When an unidentified person on Islamist side opened fire with birdshot on the marchers, and the melee erupted, according to an Associated Press cameraman. Security forces fired tear gas at the Brotherhood supporters, but when the two sides continued battling, they withdrew. Protesters later broke into the building and began to trash it. Online video posted by witnesses showed a protester carrying a gun who appeared to be shooting at the Brotherhood building.

    uch of the violence was in the provinces of the Nile Delta, north of Cairo.

    Protesters stormed an office of the Brotherhood, attacked members inside, injuring 10, and set the office on fire in the city of Shubrakheit, the state news agency said. Others stormed a Brotherhood office in the coastal city of Baltim, destroying electronic equipment, and another of the group's branches was torched in the city of Aga.

    Hundreds of protesters in the city of Bassioun threw stones at Freedom and Justice Party offices, tearing down the party sign.

    The Brotherhood says at least five of those killed this week were its members. Some people "think they can topple a democratically elected President by killing his support groups," el-Haddad said earlier on his Twitter account.

    There were reports of violence from the Islamist side in the Delta as well.

    At least six people were injured when an anti-Morsi march was attacked by the president's supporters in the city of Samanod, according to a security official. Attackers fired gunshots and threw acid at the protesters as they passed the house of a local Brotherhood leader, the official said.

    The opposition has said it will bring millions into the streets across Egypt, and more violence is feared. Already, six people have been killed in clashes this week, including Friday's deaths.

    The U.S. is deeply concerned by developments in Egypt, where clashes have broken out ahead of planned mass protests against the government headed by Islamist President Mohammed Morsi. At least six Egyptians have been killed in days of clashes ahead of nationwide protests Sunday demanding Morsi's removal.

    One administration official told Fox News, “We call on the Egyptian government to be responsive to the concerns of its people. President Morsi, as Egypt's first democratically-elected leader, has a special responsibility to reach out to all political groups and try to build consensus through compromise.

    "Democracy requires compromise and concessions on everyone's part, and Egypt's democratic transition is no different.  We hope that all Egyptians will find a way to work together peacefully to address the contentious issues facing Egypt now."

    The Associated Press contributed to this report