Former Egyptian president Hosni Mubarak has been released from prison and flown by helicopter to a military hospital.

Television pictures showed the 85-year-old leaving Torah prison on the southern outskirts of Cairo and landing minutes later in the nearby suburb of Maadi.

He is expected to be placed under house arrest at the hospital until his retrial on charges of ordering the killing of protesters.

The move was ordered by Egyptian Prime Minister Hazem el Beblawi as part of emergency measures put in place this month.

Mubarak, who is believed to be suffering from a heart condition, was sentenced to life in prison last year for failing to prevent the deaths of demonstrators during the 2011 uprising that led to his downfall.

An Egyptian court ordered his release on Wednesday, with his next hearing expected to take place on Sunday.