CAIRO — Mohammed Morsi, in office only a year as the first democratically elected leader of Egypt, was rousted from power by the military Wednesday as a euphoric crowd in Tahrir Square cheered his exit.
The former leader was placed under house arrest at the Republican Guard Club, a senior adviser to the Freedom and Justice Party and spokesman for the Muslim Brotherhood said. Most members of the presidential team have also been placed under house arrest.
Egyptian security forces also arrested the head of the Muslim Brotherhood's Freedom and Justice Party and another of the movement's top leaders.
The commanding general of the armed forces, Gen. Abdel Fattah al-Sisi, said on Egyptian television that the military was suspending the constitution, which Morsi pushed through and which many Egyptians saw as slanted toward Islamists.
"The armed forces couldn't plug its ears or close its eyes as the movement and demands of the masses calling for them to play a national role, not a political role as the armed forces themselves will be the first to proclaim that they will stay away from politics," al-Sisi said.
He added that the head of the constitutional court, Adli Mansour, would be the acting president, with new elections to be held later. The general said that the military did not have designs on controlling the country’s politics but would “never turn a blind eye to the aspirations of the Egyptian people.”
He spoke alongside a leading Sunni Muslim cleric and the head of Egypt’s Coptic Christians, as well as a prominent political opponent of Morsi — Mohamed ElBaradei, the former head of the U.N. nuclear weapons agency.
Armored vehicles, tanks and troops deployed throughout the Egyptian capital, including near the presidential palace. The army seized the headquarters of the state television and the state-run newspaper, which reported that Morsi had been told he was no longer president.
A statement on Morsi's Facebook page described the army's move as a "military coup."
Mansour will be sworn in as interim head of state Thursday.
The United States will continue to monitor the "very fluid situation" in Egypt, President Barack Obama said in a statement Wednesday night.
"We are deeply concerned by the decision of the Egyptian Armed Forces to remove President Morsy and suspend the Egyptian constitution," the statement read. "I now call on the Egyptian military to move quickly and responsibly to return full authority back to a democratically elected civilian government as soon as possible through an inclusive and transparent process, and to avoid any arbitrary arrests of President Morsy and his supporters."
U.N. Secretary-General Ban Ki-moon called for calm and restraint, as well as the preservation of rights such as freedom of expression and assembly.
"Many Egyptians in their protests have voiced deep frustrations and legitimate concerns," he said in a statement that did not condemn the Egyptian armed forces' ouster of Morsi.
"At the same time, military interference in the affairs of any state is of concern," he added. "Therefore, it will be crucial to quickly reinforce civilian rule in accordance with principles of democracy."
Security forces, meanwhile, raided the Cairo offices of Al Jazeera's Egyptian television channel and detained at least five staff members. Four were later released, the channel said.
Karim El-Assiuti, a journalist at the station, told Reuters his colleagues at the Al Jazeera Mubasher Misr channel were arrested while working in the studio. The station was prevented from broadcasting from a pro-Morsi rally and its crew there was also detained, he said.
Authorities also shut down three Islamist-run TV stations, including one operated by the Muslim Brotherhood.
The State Department warned U.S. citizens to defer travel to Egypt and told Americans already living in Egypt to depart "because of the continuing political and social unrest."
Morsi was elected a year ago after Egyptians ousted Hosni Mubarak, the autocrat who had ruled for almost three decades. Egyptians hoped he would build a more pluralistic and tolerant country.
Instead, Egyptians have been frustrated by a struggling economy and poor services and infuriated by what they see as power grabs by Morsi — stifling the judiciary and forcing through a constitution that favored Islamists and ignored minorities.
“Now we want a president who would really be the president of all Egyptians and will work for the country,” Said Shahin, a 19-year-old protester in Tahrir Square, told The Associated Press.
The ouster will remake the politics of the Middle East at a volatile time. Egypt is the most populous country in the region, has a peace treaty with Israel and is a partner of the United States.
On Tuesday, Morsi gave a loud, passionate, 45-minute speech to the country, blaming loyalists of Mubarak for fighting against democracy and refusing to step down. He vowed to die for his cause.
“I am prepared to sacrifice my blood for the sake of the security and stability of this homeland,” he said.
On Wednesday, as the military appeared to be taking control of parts of Cairo, advisers to Morsi said the generals were staging a coup and subverting the will of the people.
In Tahrir Square, however, the military announcement hours later was greeted with jubilation reminiscent of the first days of the Arab Spring two years ago. Tens of thousands of people shot fireworks, sang, danced, chanted and waved Egyptian flags.
Before they deposed Morsi, Egyptian military officials assured the U.S. that the military would not assume long-term control of the government, and ensured the safety of the U.S. Embassy, personnel and all Americans in Egypt, U.S. officials told NBC News.
Defense Secretary Chuck Hagel and the chairman of the joint chiefs of staff, Gen. Martin Dempsey, had been in contact with their counterparts in the Egyptian military over the past week.
The military had given Morsi 48 hours to step aside or share power. In a statement posted to Facebook in the final hours before the deadline, the military swore its own fight to the death.
“We swear to God to sacrifice with our blood for Egypt and its people against any terrorist, extremist or ignoramus,” the military said in a statement. “Long live Egypt and its proud people.”
At least 16 people were killed during the day and more than 200 injured in clashes, primarily around Cairo University.
The crisis could have a significant effect on the global economy. The benchmark price of crude oil for delivery in August rose above $102 in electronic trading on the New York Mercantile Exchange, the highest since early May last year.
Egypt’s control of the Suez Canal — one of the world's busiest shipping lanes, which links the Mediterranean with the Red Sea — gives it a crucial role in maintaining global energy supplies.
Reuters and The Associated Press contributed to this report. Ayman Mohyeldin reported from Cairo, Ian Johnston reported from London and Becky Bratu and Erin McClam from New York.