Egypt's former president Mohammed Morsi, who was ousted by the army in 2013, has died after fainting in a courtroom, said media reports citing state TV.

Morsi, a former top figure in the now-banned Islamist movement Muslim Brotherhood, was at a session over accusations of espionage.

He was overthrown following mass protests a year after he took office as the country's first democratically elected leader, reported BBC.

He had remained in custody since then.

"The body has been transferred to a hospital and necessary procedures are under way," Nile News TV said.

According to Al Ahram newspaper, Morsi, 67, fell into a coma after attending a session in his trial over charges of espionage.

In the session he was granted permission to address the judge, Al Ahram said. After the session was adjourned, the former president fell unconscious and died.

The former president was transferred to an unnamed hospital, stated the report.

Morsi, Egypt's first freely elected leader, came to power following the 2011 popular revolution that toppled longtime autocrat Hosni Mubarak.

Born in Giza's al-Ayat, Morsi was an academic and engineer who rose to seniority in Egypt's Muslim Brotherhood, before winning the 2012 presidential election as his group's candidate.

He was removed from power in a 2013 military coup led by his defence minister, Abdel Fattah El-Sisi, who then replaced him as president.