Cairo: Muslims and Christians clash in Imbaba
At least five people have been killed and dozens more wounded during clashes between Muslims and Christians in Cairo.
The clashes started after a crowd of Muslims attacked a church, demanding it hand over a women they believe had converted to Islam.
It took police and soldiers some hours to bring it under control.
Clashes between Muslims and Christians have continued into the post-Mubarak era, after harmony in the revolution.
The recurrence of yet another serious outbreak of communal violence - as the military government leads a faltering transition to democracy - is a worrying development for Egypt, the BBC's Jonathan Head in Cairo says.
Eyewitnesses said several hundred conservative Muslims - belonging to the Salafist movement - gathered at the Coptic Saint Mena Church in the heavily-populated north-western Cairo district of Imbaba.
They were protesting over allegations that a Christian woman was being held there against her will because she had married a Muslim man and wanted to convert to Islam, Egypt's official Mena news agency reports.
Shouts were exchanged between church guards, people living near the church and the protesters, which developed into a fully-fledged confrontation involving gunfire, firebombs and stone-throwing.
The church and some nearby homes were set alight, and it took several hours for the emergency services and the military to bring the situation under control.
"I just left one young man dead inside the church," one man, a Christian, was quoted as telling Reuters journalists.
A parish priest, Father Hermina, told the AFP news agency that the group had attempted to storm the church earlier in the day.
But one Muslim protester told the news agency that they had first been fired upon by the Copts.
"We were peaceful," said the man, who gave his name as Mamduh. "We won't leave until they give up their weapons and the people who killed us are tried."
As well as five dead, at least 50 people were reported to have been wounded.
Nearby in the same district, Muslim protesters threw firebombs at another church, setting it on fire. There were no of reports of any casualties but the al-Azraa church was severely damaged in the blaze.
Similar claims about women being held against their will have been made before by Salafist groups, who have become more assertive in the post-Mubarak era, our correspondent says.
In March, 13 people died in similar clashes in another neighbourhood. Last month, demonstrators in the southern city of Qena cut all transport links with Cairo for a week in protest over the appointment of a Christian governor.
Coptic Christians account for about 10% of Egypt's population, and have long complained of state discrimination against them.
Now they are expressing fears for their safety if hardline Muslims do well in the election scheduled for September, our correspondent reports.