Police in the Egyptian capital, Cairo, have clashed with protesters angry at what they say is the rushed drafting of a new constitution and by President Morsi's recent extension of his powers.
Mohammed Morsi adopted sweeping new powers in a decree on 22 November, and stripped the judiciary of any power to challenge his decisions.
He has also called a nationwide referendum for 15 December on a new constitution, which opponents say has been rushed through and fails to protect the rights of minorities, particularly women.
Mr Morsi, who narrowly won Egypt's first free presidential election in June, says he will give up his new powers once a new constitution is ratified.
But his actions have brought out thousands, both his supporters and his opponents, in recent days.
Several newspapers refused to go to press on Tuesday, or printed blank front pages, in protest at what they say is the lack of press freedom in the constitution.