Prosecutors have ordered the detention for 15 days of nine men suspected of killing a taxi driver during a pro-Muslim Brotherhood protest in the Nile Delta.

On Monday, 32-year-old Mohamed Osman was stabbed to death in Mansoura while driving his taxi through a rally in support of ousted Islamist president Mohamed Morsi.

The Brotherhood-aligned Rasd news website said Osman's taxi was set on fire after he sped into the rally, injuring a woman who had to be hospitalised. Rasd posted a video allegedly showing the injured woman.

The coroner's report said Osman died of a deep stab wound to the chest. He also suffered several shallower wounds to his back and neck.

Since Morsi's ouster in July, his supporters have been staging near-daily protests calling for his reinstatement. Their demonstrations have often descended into street clashes with security forces or civilians with anti-Brotherhood sentiments, leaving hundreds of dead.