More than 140 people have been confirmed killed after Egyptian security forces opened fire as they tried to clear two protest camps loyal to deposed president Mohamed Morsi in Cairo.

A month-long state of emergency has been declared as violence spread from the capital to other parts of the country including the Mediterranean city of Alexandria.

A curfew from 7pm to 6am has been declared in Cairo, according to reports, as well as ten other provinces including Alexandria and Suez.

The health ministry put the number of dead in Cairo at 149, with hundreds more injured. But the Muslim Brotherhood claimed hundreds had been killed.

Egypt’s vice president, Mohamed ElBaradei, has now announced his resignation.

Sky’s Middle East Correspondent Sam Kiley, reporting from inside the Rabaa al Adawiya camp in the capital, said it was “under very heavy gunfire” and was a “massive military assault on largely unarmed civilians in very large numbers”.

He said government forces were using machine guns, snipers, AK-47 and M16 rifles and were firing into the crowd.

Kiley added: “There are machine gun rounds, and snipers on the roof, that are preventing people from getting any closer to the field hospital (in the camp).