Muslim villagers reportedly accused 35-year-old Abdo Adel of publishing a post on his Facebook page that was an insult to Islam.
A local source that wanted to remain anonymous told World Watch Monitor that Christians in Menbal - 225km south of Cairo - were afraid to leave their homes despite security forces patrolling the streets since the unrest began on Monday.
Girgis Shawky, 32 said: "The Muslim extremists in our village and the nearby villages incited the Muslim villagers against us... they began pelting the Coptic-owned houses with stones and bricks, while shouting 'Allahu akbar' [Allah is the greatest] and chanting slogans against Copts, such as 'We will displace you and the priest from our village, oh kaffir [infidels], oh the worshipers of the cross, oh defiled people'."
Police have arrested 90 Muslim villagers on charges of mobbing, attacking Coptic houses and the police, and inciting sectarian strife.
Hany Adly, a Copt from the village told World Watch Monitor: "All of us [Copts] have stayed in our homes. We are afraid to get out to the village streets. There is a state of panic and fear among all of us here. I cannot open my shop.
"Despite the presence of security forces in the village, we are still receiving threats from our Muslim neighbours. They say they will take revenge on all of us as soon as the security forces leave the village. We are afraid that they will attack us this Friday after their noon prayers."
A curfew has been imposed from 8pm until 8am.
Stay up to date with the latest news stories from a Christian perspective. Sign up to our daily newsletter and receive more stories like this straight to your inbox every morning.