Thirteen people were killed in violence between Christians and Muslims in Cairo Tuesday night, the state news agency reported Wednesday.
The agency quoted a senior health ministry official as saying 110 people were wounded in the violence.
Triggering the violence was a Christian protest over an arson attack on a church in Helwan south of Cairo.
Christians protesting over the attack on the church had blocked a main highway south of Cairo and violence started after Muslims who wanted to pass through clashed with the protesters, a security source said.
Gasoline bombs and rocks were thrown. At least one of the dead Christians died from a bullet to the back, but it was unclear who had fired it. The army had fired into the air to disperse protesters.
Coptic Christians make up about 10 percent of Egypt's population of 80 million.
Tensions between the communities which appeared to evaporate during the mass uprising against President Hosni Mubarak have resurfaced in recent days, posing a challenge for the country's interim military rulers.
Islamists protested outside the prime minister's office Tuesday over the case of two women they believe are being held against their will in churches after converting to Islam.
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