CAIRO, July 3 (Reuters) - Three people were killed and about 90 wounded in clashes near Cairo University between supporters of President Mohamed Mursi and security forces, an aide to Egypt's health minister told Reuters.

Witnesses heard shotgun and rifle fire and teargas enveloped the area. Television pictures showed ambulances taking away casualties, small fires burning and hundreds of men, many with the beards typical of Mursi's Islamist supporters, some of them weeping and others chanting slogans.

Some held up rifle and shotgun cartridges to the camera. Another man waved his bloodied hand. (Reporting by Yasmine Saleh; Editing by Alastair Macdonald)