Turkey's Erdogan slams 'tyrant' Sisi in tribute to Egypt's 'martyr' Mohamed Morsi

Turkish President Recep Tayyip Erdogan has paid tribute to ousted Egyptian president Mohamed Morsi who died suddenly on Monday, calling him a "martyr".

"May Allah rest our brother Morsi, our martyr's soul, in peace," said Erdogan, who had forged close ties with Morsi.

Erdogan proceeded to describe incumbent Egyptian President Abdel Fattah al-Sisi as a "tyrant" who "has executed at least 50 Egyptians". 

The Turkish leader also extended his prayers to Morsi's "thousands of friends" in prison.

"My condolences to the people of Egypt, to all my brothers who walk the same road as him," he added.

Morsi, who was Egypt's first democratically-elected president,  died in a Cairo hospital after fainting during a session in court, judicial and security sources said.

"He was speaking before the judge for 20 minutes then became very animated and fainted. He was quickly rushed to the hospital where he later died," a judicial source said.

The official Al-Ahram news website also reported the death of Morsi, who was elected president in 2012 but spent just one turbulent year in office before the army toppled him in July 2013.

The Islamist leader had been in prison since his ouster on trial for several cases including for spying for Iran, Qatar and militant groups such as Hamas in the Gaza Strip. He was also accused of plotting terror acts.

The charges were widely seen as trumped-up and politicised. Egypt's current government has contacts with Hamas and mediates between them and Israel.