Protesters threw stones and bottles at the Egyptian prime minister's motorcade on Saturday as he tried to enter Cairo's Tahrir Square after overnight clashes nearby and at the presidential palace, media reported.
Dream Live, a private television station, reported that Prime Minister Hisham Qandil left the scene after the attack. His office said in a statement, without elaborating, that he had been "confronted by youths and troublemakers."
"I preferred to avoid a confrontation between them and security personnel," Qandil said later on his Facebook page.
Dozens of protesters remained in the square on Saturday after several thousand demonstrators rallied there on Friday against Islamist President Mohamed Morsi. Hundreds of people had clashed with police in a nearby street.