An Egyptian court on Saturday sentenced 28 people to death for their involvement in the killing of a top prosecutor two years ago, security and judicial officials said.

Hisham Barakat was killed in 2015 when a car bomb struck his convoy in Cairo after militants call for attacks on the judiciary to avenge a crackdown on them.

No group claimed responsibility for the attack, but police later said they had arrested the perpetrators, charging they were members of the outlawed Muslim Brotherhood.

The court also sentenced 15 defendants to life in prison in the same case, while a further eight received 15 years, and 15 others were handed 10 years, the officials said.

The death sentences have already been approved by the mufti, Egypt's official interpreter of Islamic law, whose opinion is legally required but not binding. The rulings can still be appealed.

Egyptian courts have sentenced hundreds of Morsi supporters to death since the military overthrow his government, but many have appealed and won new trials. Morsi and other top figures of his Muslim Brotherhood have also faced trial.