Six Irish workers are believed to be in Libya's second city where government troops reportedly opened fire on protesters with machine guns.
The Department of Foreign Affairs was in touch with the group in Benghazi through their company but lost contact on Saturday after internet and telephones were cut off.
The group is understood to be safe in a secure compound but unable to travel out of the city because of safety concerns.
A department spokesman said it is not clear if they remain in the city.
"We are trying to make contact with six Irish who we understand may be in Benghazi," he said. "We understood yesterday that where they are is safe, but it is not safe to travel on roads so the recommendation was to remain where you are for now."
It is believed the group has sufficient transport to get out of the city but the roads are currently too dangerous to travel on.
There are 40 Irish citizens in Libya, with the bulk in the capital Tripoli. Irish diplomats are liaising with EU officials in Libya to get the six Irish to safety in Tripoli.
The Department of Foreign Affairs has warned against non-essential travel to the North African state after protests broke out last week.
It advised people in Benghazi and the surrounding area or other large cities to follow the news on TV and radio and not to go out in central Benghazi or other areas where demonstrations may take place.
"We are advising all citizens to take extra precautions and to avoid political gatherings and demonstrations over the following days," the department said on its website. "Follow news reports and be alert to developments in Libya and elsewhere in North Africa and the Middle East that might trigger public disturbances."