Security forces arrested 76 Muslim Brotherhood members during Friday rallies staged by supporters of ousted president Mohamed Morsi, Egypt's Interior Ministry said in a statement.The ministry did not reveal where the Brotherhood members were arrested, but according to security officials, eight of them were detained in the central Fayoum province and ten others in Alexandria.The ministry also said two policemen had been injured in Giza during clashes with protesters.Earlier Friday, the Health Ministry had said that six people were injured in clashes between security forces and Morsi supporters, although earlier reports had said at least one demonstrator had been killed.In its statement, the ministry asserted that a total of six people had been injured during "gatherings" in Egypt's Giza, Sharqiya and Fayoum provinces.Earlier in the day, a source from the pro-democracy National Alliance for the Defense of Legitimacy told Anadolu Agency that Mustafa Kamal Yassin, 20, had been shot dead during clashes that erupted after security forces dispersed a pro-Morsi rally in Alexandria's Al-Hanovel district. A medical source confirmed that Yassin had been killed by live gunfire.While Interior Ministry officials weren't available for comment, they usually deny using live ammunition to disperse protests.Protesters staged fresh rallies on Friday as part of an 11-day "revolutionary wave" called for by the pro-Morsi alliance to mark the third anniversary of a constitutional referendum that had represented Egypt's first free poll following the 2011 ouster of autocratic president Hosni Mubarak.Since Morsi's ouster by the army more than eight months ago, which critics describe as an unconstitutional "military coup," his supporters have continued to stage rallies on an almost daily basis to demand his reinstatement.