A priest told the Associated Press that the group were Coptic Christians from Egypt.
The gunmen went room to room in the city of Sirte in the early hours of Saturday morning.
Reports from witnesses say the men separated the Muslims and let them go free before handcuffing and driving away with the Christians.
It's not clear who is responsible for the abduction or if any demands have been made.
The city of Sirte is a hotbed for Islamic extremism and militants from there are blamed for the 2013 attack on the U.S. Consulate in Benghazi.