The mob threw stones and Molotov cocktail fire bombs at believer's homes and businesses in Kafr Dawish, 100km south of the capital Cairo, after a man in one of the familes was accused of putting pictures of Muhammad on Facebook.
Other local Muslims defended the families' homes, and police also intervened to stop the violence.
Local leaders ordered the Christian families to leave after a series of meetings, where their homes, crops and cattle were destroyed in their absence, according to anti-persecution charity Christian Solidarity Worldwide (CSW).
There were also reports ten other Coptic families' homes were set on fire.
However after intervention from Egyptian politicians and an interfaith organisation, who sent Muslim clerics to diffuse the situation, the families were able to return.
Mervyn Thomas, CSW's Chief Executive, said: "While Christian Solidarity Worldwide welcomes the positive steps taken by local authorities to secure their safe return, the eviction of the families was unacceptable.
"Their case highlights the unsatisfactory nature of reconciliation sessions, which impose ad-hoc, unjust and often un-constitutional conditions on the victims of sectarian violence, who subsequently have no recourse to judicial remedies.
"CSW urges the security forces in al-Fashn to investigate and to bring the perpetrators of this violence to justice.
"We urge the Interior Ministry and other authorities to end the use of reconciliation meetings to settle sectarian tensions, as these perpetuate impunity for the perpetrators, who face no consequences for their crimes.
"Local authorities must also ensure that the five families receive adequate and timely compensation."
