Updated

The head of Egypt's national ambulance services says one person has been killed in clashes outside Cairo's main Coptic Christian cathedral.

Mohammed Sultan said the person died of wounds from birdshots.

Sunday's clashes outside the St. Mark Coptic Orthodox Cathedral began shortly after hundreds of angry Christians left the sprawling complex to stage an anti-government march following a funeral for four Christians killed in sectarian clashes on Saturday.

Denouncing Morsi, the mourners chanted "Leave!" and "This is our country, we will not leave."

Police fired tear gas to disperse the Christians.

Soon after they left the complex, a mob, described by witnesses as residents of the area, pelted them with rocks, firebombs and birdshot, forcing them back inside the complex. They also showered the protesters with rocks from the roofs of nearby buildings, according to witness Ibrahim el-Shareef.

At least 21 people were also injured in the clashes.

Coptic Christians make up about 10 percent of Egypt's estimated 90 million people. They have long complained of discrimination.