CAIRO (AP) — An Egyptian doctor at a rally of ousted president Mohammed Morsi's supporters says the death toll from clashes with security forces has risen to 38 protesters.

Yehia Mikkia said Saturday that the total number killed in the overnight clashes is likely higher. Many casualties were transported to hospitals outside the sit-in, where the protesters have been camped for over three weeks. He said hundreds were wounded.

The clashes started after police fired tear gas to disperse hundreds of Morsi supporters who tried to extend the sit-in in eastern Cairo.

They came hours after millions took to the streets answering a call from the head of the army, who said he wanted a mandate to stop "potential terrorism" by Morsi supporters.