Cairo (CNN) -- Egypt's military deposed the country's first democratically elected president Wednesday night, installing the head of the country's highest court as an interim leader, the country's top general announced.
Gen. Abdel-Fatah El-Sisi said the military was fulfilling its "historic responsibility" to protect the country by ousting Mohamed Morsy, the Western-educated Islamist leader elected a year ago. The country's constitution has been suspended, new parliamentary elections will be held and Adly Mansour, the head of the country's Supreme Constitutional Court, will replace Morsy, El-Sisi said.
Mansour will have the power to issue constitutional declarations during the interim period and will "establish a government that is a strong and diverse," the armed forces chief said. He said Morsy "did not achieve the goals of the people" and failed to meet demands to share power with opponents who thronged the streets of Cairo and Tahrir Square.
Those crowds erupted as the announcement was made on Egyptian television shortly after 9 p.m. (3 p.m. ET). But Morsy supporters gathered in another Cairo plaza vowed to oppose the coup, chanting "Down with military rule" and "The square has a million martyrs." And in statements posted on the presidential Facebook and Twitter pages, Morsy said his ouster would be "categorically rejected by all the free men of our nation."
"The president -- who is also the supreme commander of the armed forces -- tells all citizens, civilians and military, leaders and soldiers, must abide by the constitution and should not respond to the coup which brings Egypt behind," he said. "Everyone must take responsibility before God, people and history."