The clashes first erupted on Friday during protests on the anniversary of the dispersal of two Cairo sit-ins.
Emergency services chief Mohammad Sultan said Saturday that the five had been killed in the capital the day before. He said the violence left 34 people wounded.
This raises the death toll from two days of clashes during protests to nine people.
The demonstrations come on the one-year anniversary of the Aug.14 break-up of two protest camps by supporters of toppled President Mohammad Morsi.
Morsi supporters have been demonstrating since his ouster last summer. Their protests, however, have sharply decreased amid a security crackdown that left tens of thousands detained.
RA/SHI