One person has been killed in clashes outside Cairo's main cathedral following the funerals of four Coptic Christians killed in religious violence on Thursday.
Mourners leaving St Mark's Cathedral clashed with local residents. Police fired tear gas to break up the violence on Sunday. More than 80 people were injured, the state news agency said.
The health ministry said one Christian man was killed. The ambulance service said he was struck with birdshot.
Mourners inside the church had earlier chanted slogans against Egypt's Islamist President Mohammed Morsi, the BBC reports.
Witnesses told local television stations that the violence started when a mob attacked mourners as they exited the cathedral, pelting them with stones and petrol bombs. There was initially little police presence.
The Christians responded by throwing stones back, the witnesses said, until police arrived and attempted to quell the unrest, firing tear gas into the cathedral compound.
Egypt's state news agency said the streets around the cathedral had seen "on-and-off" clashes between Christians and "unidentified persons".
It said a fire had started in a building adjacent to the cathedral, but the blaze had since been extinguished.
It also said President Morsi had denounced the violence in a phone call to the head of the Pope Tawadros II, the head of the Coptic Christian church.