An Egyptian student was killed during clashes between anti-government protesters and residents in the coastal city of Alexandria, as demonstrations gathered pace days before the anniversary of the 2011 uprising.
The Freedom and Justice Party, the political wing of the outlawed Muslim Brotherhood, identified the dead woman on Friday on its Facebook page as 17-year-old Sondos Rida Abu Bakr and accused security forces of shooting her during a demonstration, Reuters news agency reported.
A security official in Alexandria said several people were wounded on Friday in clashes between protesters and local residents but denied that security forces had opened fire to disperse demonstrators.
At least 20 people were also arrested in Alexandria on Friday and 68 the previous day, security sources said.
Demonstrations took place in several parts of Egypt on Friday, with Brotherhood supporters calling for protests to mark four years since the January 25, 2011 revolt that toppled veteran autocrat Hosni Mubarak and led to democratic elections.
Also on Friday, a bomb in Cairo wounded four policemen and a civilian, officials said.
It was the second in the capital in as many days, after an explosion wounded a police officer late on Thursday outside the Al-Qubba presidential palace.
The bomb exploded in the Alf Maskan district, where the injured policemen were stationed to confront expected protests by opposition activists.
Egypt has been rocked by waves of nonviolent protests, as well as some bombings and shootings, since the military toppled the first democratically-elected president Mohamed Morsi, a member of the Muslim Brotherhood.
Abdel Fattah el-Sisi, the army chief behind Morsi's removal, became president in May and launched a crackdown that has seen Egypt's oldest Islamist movement driven underground and thousands of its members along with other opposition activists arrested.
Human rights groups say a law restricting protests and other security legislation enacted by Sisi in the absence of a parliament have rolled back freedoms won in the 2011 uprising.
Liberal activists, including many who supported Morsi's removal, have since found themselves on the wrong side of Egypt's new rulers, with many facing trial for taking part in small protests.
Sisi said this week Egyptians had the right to protest but cautioned that demonstrating could harm the economy.