"Nineteen people were killed – among which is a policeman – and 82 others were injured on Sunday," Heath Ministry spokesman Hossam Abdel-Ghaffar told The Anadolu Agency.
"Two other policemen are hospitalized in a critical condition after having come under fire in Giza province," Abdel-Ghaffar said, dismissing earlier reports that the pair were killed in the attack.
A security source who declined to be named told AA that 429 people were arrested during clashes across Egypt on Sunday.
Four years to Sunday, thousands of Egyptians took to the streets and eventually descended on Tahrir Square in downtown Cairo to protest police brutality.
With many protesters killed and wounded by security forces, the demonstrations soon developed into a full-fledged popular uprising nationwide that demanded regime change.
Mubarak had to step down on Feb. 11 of the same year under public pressure, handing over power to the military.
A transitional phase ended with the election of Mohamed Morsi, Egypt's first democratically elected leader.
Morsi was removed by the military on July 3 of 2013 following mass demonstrations against his one-year rule.
His supporters, however, describe his removal as a military coup while others insist it was a popular military-backed uprising.
Thousands of Morsi supporters have since been killed or jailed amid a massive crackdown on dissent in general.