Witnesses say Egyptian protesters clashed with security forces in Cairo Friday after military police allegedly arrested and beat an activist.

Hundreds of protesters hurled rocks and firebombs at military police, who responded by throwing rocks, using water cannons and firing shots into the air.

Local media reported a government building on fire as the clashes continued through the morning.

Protesters say the demonstrations broke out following reports that police beat a young man who was part of a sit-in that began in November outside the Cabinet building.

Activists say security forces on Friday tried break up the protesters, who are calling for an end to military rule.

Several people were reportedly wounded in the clashes.

The violence comes as Egyptians await the official results of the second round of parliamentary elections held this week. Islamist parties appeared to be extending their already overwhelming electoral gains. Elections officials are expected to announce final results Friday or Saturday.