The head of the Egyptian army has appeared live on television, announcing the suspension of the constitution.
General Abdul Fattah Al-Sisi, flanked by religious and military leaders, said the chief justice of constitutional court would take the powers of the presidency.
His announcement means President Mohammed Morsi is no longer in power.
Anti-Morsi protesters in Cairo’s Tahrir Square gave out a huge cheer in response to the speech.
The move follows four days of mass street protests against Mr Morsi, and an ultimatum issued by the military which expired on Wednesday afternoon.
The current whereabouts of Mr Morsi are unknown.