Egyptian riot police have fired tear gas to disperse hundreds of supporters of ousted Islamist president Mohammed Morsi protesting as the country marks the third anniversary of the 2011 uprising.

Egyptian authorities have authorised police to use deadly force to protect themselves and key state institutions from attacks.

Egypt’s top security body warned that the clock was ticking for a peaceful end to the stand-off over sit-ins by supporters of ousted president Mohammed Morsi, suggesting authorities would break up the protests unless mediation produced results soon.

Ousted Egyptian president Mohamed Morsi has been detained over alleged contacts with Hamas to help in his escape from prison in 2011, the country’s official news agency reported today.