The US has warned Americans not to travel to Egypt and has told non-emergency diplomatic staff to leave, as clashes continued in the country.
The state department also urged US nationals in Egypt "to remain alert".
The warning came as at least 3 people - including a US citizen - died in clashes between supporters and opponents of President Mohammed Morsi.
Tensions have been rising ahead of a mass rally planned by the opposition on Sunday, calling Morsi to step down.
His supporters are stressing what they see as Morsi's "legitimacy", rejecting the opposition's demand.