A Mansoura criminal court sentenced nine defendants to death on Monday for the murder of an off-duty police officer who was part of a judge's security detail.
Fourteen others were sentenced to life in prison in the same case, while another defendant was sentenced to ten years in prison.
Police sergeant Abdallah Metwally was killed in February 2014 while returning to his home in Daqahliya governorate, after concluding his shift guarding the house of a judge.
The judge, Hussein Kandil, was adjudicating a court case in which former president Mohamed Morsi was one of the defendants.
The defendants convicted on Monday, who were arrested at an apartment in Mansoura, were charged with killing Metwally, as well as committing terrorist acts against army and police personnel, and possessing weapons and explosives.
The verdict can still be appealed.
Since the ouster of Morsi in July 2013, there has been a wave of attacks against police and army targets. Some judicial figures have also been targeted, most notoriously the country's top prosecutor, Hisham Barakat, who was killed by a car bomb in Cairo in June.
Morsi is currently being tried in a number of cases on various criminal charges including espionage. He received a death sentence after being convicted of breaking out of prison and related charges, in an incident from 2011. He also received a life sentence in a separate case after being found guilty of spying for Hamas.
Both cases are currently under appeal.