At least two people were killed and six injured on Sunday in violent clashes in Matariya in eastern Cairo, reported Al-Ahram Arabic website.
The site also reported that a policeman was also killed in the clashes between protesters and police, but it was not immediately clear if he was one of the two deaths cited.
It is also not clear if the Matariya victims are among the death toll of 11 announced by the health ministry after violence erupted in a number of cities on the fourth anniversary of the 2011 revolution.
Rallies in support of ousted president Mohamed Morsi are common in Matariya, as are clashes with police.
Pro-Muslim Brotherhood youth coalitions had called for mass protests in the area on Sunday, resulting in a large number of demonstrators.
In downtown Cairo, clashes erupted on Sunday between protesters and a number of supporters of El-Sisi during a protest at the Journalists Syndicate.
The protest was organised to demand retribution for those injured in the 2011 revolution. Demonstrators had chanted for retribution, as well as chanting against military rule and against El-Sisi.
Clashes started when a group of El-Sisi supporters began to hurl rocks at the protesters.
Security forces dispersed the clashes, firing teargas.
A number of smaller protests were also dispersed around the capital, including in Maadi, Helwan and Giza's Talybia.