The first Egyptian democratically elected president died  on Monday died of a heart attack after collapsing in a court in Cairo while being tried on allegations of spying, officials and a medical source said.

Following mass demonstrations against his rule, the 67-year-old Morsi, a top figure in the now-banned Muslim Brotherhood, had been in prison since being overthrown by the army in 2013 after scarcely a year in power.

His death is likely to accumulate global pressure on the Egyptian government over its record of human rights, particularly in prisons where thousands of Islamists and secular activists are kept.

The public prosecutor said Morsi had collapsed soon after addressing the tribunal in a defendant's cage and was declared dead at 4:50 p.m. in hospital. (1450 GMT). It said that original inspections on his body had shown no indications of the latest injury.

The Muslim Brotherhood defined Morsi's death as a "full-fledged assassination" and called on masses to gather around the globe at his funeral in Egypt and outside Egyptian embassies. Morsi's family had earlier said his health had deteriorated in jail and they were rarely permitted to visit.

It was believed that Morsi, who was diabetic and suffered from high blood pressure, had received medical therapy in a private hospital and in Cairo's police hospital, denying being deprived of medical care.