|Libya has been plagued by instability as rival groups fight for control of the country|
Eyewitnesses in the city of Sirte said suspected Islamist militants went to a residential compound late at night and asked to see identification papers.
Christians were then separated from the Muslims before reportedly being handcuffed and kidnapped.
It is the latest in a series of attacks on Egyptian Christians in Libya.
One witness said 15 masked gunmen went from room to room in the residential complex at about 02:30 local time (04:30 GMT) on Saturday morning.
"They had a list of full names of Christians in the building. While checking IDs, Muslims were left aside while Christians were grabbed," Hanna Aziz told the AP news agency.
Mr Aziz said he survived because he heard his friends screaming and didn't open his door. "I am still in my room waiting for them to take me. I want to die with them,"
All of those taken are believed to be men.
|Libyan cities of Tripoli, Benghazi and Sirte and Egypt's capital Cairo|
There was also an attack on the home of an Egyptian Coptic doctor in Sirte in early December, in which he and his wife were killed. Local reports said the couple's daughter was also found dead after being abducted. The daughter was 18 years old, and I'm sure she went through Hell before being murdered. The abductors did leave her two younger sisters behind, thank God.
Libya is home to a very large community of both Muslim and Coptic Egyptians, with most working in the construction sector.
|Coptic church near Misrata, Libya|
Rival militias now control most of the country including the two largest cities, Tripoli and Benghazi, and Sirte has become a safe haven for Islamist fighters.