Clashes broke out between Muslims and Coptic Christians in Alexandria in Egypt, after the funeral of a Coptic worshipper killed in church on Friday.Police fired tear gas and tried to separate the groups, who threw stones and attacked each other with sticks.
This followed the funeral of Nushi Atta Girgis, 78, who died after being stabbed in one of three knife attacks at Alexandria churches.
Christians have accused the government of failing to protect them.
Mourners shouted anti-government slogans as the funeral procession - attended by an estimated 3,000 people - turned into a protest outside the church where the funeral was held.
At least 15 people were injured and four vehicles were burned out, an interior ministry source said.
'Crushed by Muslims'
The government has announced the arrest of a "deranged" man it says was responsible for all the attacks, but some Copts believe they were carried out simultaneously as part of an anti-Christian plot by extremist Muslims.
A judge remanded Mahmoud Salah-Eddin Abdel-Raziq, 25, into custody.
"Certain papers speak of a madman. I don't believe a word. It is propaganda to silence us and to make us believe it is an individual incident," said Karim, a 78-year-old Copt at the funeral.
"We have always been peaceful, but we are always crushed by the Muslims," said 30-year-old Girgis Mina. "If the state does not protect us, we will do it ourselves."
Christians make up 10% of the Egyptian population and have complained of harassment and discrimination.
Some Copts argue that previous attacks on them have gone unpunished or have drawn light sentences.
Most Christians in Egypt are Copts - Christians descended from the ancient Egyptians.
Their church split from the Eastern Orthodox and Roman Catholic churches in 451AD because of a theological dispute over the nature of Christ, but is now, on most issues, doctrinally similar to the Eastern Orthodox church.
Verbum diaboli Manet in Episcopis Calvinus et Mahometus
Saturday, April 15
A rebirth of Islam's Golden Age of Tolerance toward non-Muslims
Just as Allah and his false prophet command. Clashes follow Egypt Copt funeral:
From the quill-pen of your friendly, neighborhood
Amillennialist