Around 30 people have been reported killed and scores of others injured as violence has surged in Egypt in the wake of the ouster of Islamist-backed President Muhammad Morsi.
As clashes between supporters and opponents of Morsi raged in Cairo, state-run television reported a death toll of 17.
Later, officials said 12 people had been killed in the city of Alexandria in clashes between the two sides.
The violence came as tens of thousands of supporters of the Muslim Brotherhood rallied July 5 to demand the reinstatement of Morsi.
Violence was reported to have eased in Cairo after the army sent in armed personnel carriers.
In another development, the Interior Ministry said the powerful deputy head of the Muslim Brotherhood, Khairat el-Shater, was arrested on allegations of inciting violence.
The Muslim Brotherhood has rejected the military-backed interim government that has been set up since Morsi, Egypt’s first democratically elected president, was removed from power on July 3, almost exactly one year after he took office.
The Islamists say the military carried out a brazen coup of an elected leader.
The military says the interim government is supposed to pave the way for new elections.
In Washington, the U.S. State Department condemned the clashes and called on all Egyptian leaders to prevent further violence.
The United States again did not use the word "coup" to describe the events in Egypt.
Under U.S. law, Washington would be forced to halt its $1.5 billion in annual aid to Egypt in the event of a military overthrow of a legitimately elected government.
The Egyptian ambassador to the United States, Muhammad Tawfik, defended the events of recent days.
"This was a situation in which the vast majority of Egyptians took to the streets -- 22 million petitions were filled in and all they asked for was early elections," Tawfik said in an appearance on the U.S. PBS television program "Newshour." "They didn't ask for the military to take over. They asked for early elections."
The ambassador added: "Now, President Mursi and his supporters, what they did is they mobilized, they stirred people's feelings up and basically they encouraged their supporters to face the other demonstrators, so there was no option for the military and for the rest of Egyptian society but to intervene before terrible clashes and escalation would run out of control."
Morsi’s ouster came after millions of Egyptians took to the streets to demonstrate against the president's links to Islamists and his government’s failure to reverse Egypt’s economic decline.
The country has seen falling foreign investment levels, tourism, and standards of living in the turmoil that has gripped the nation since longtime ruler Hosni Mubarak was toppled in a popular revolt in February, 2011.
Based on reporting by AP, AFP, and Reuters