The Department of Foreign Affairs has said that it is trying to establish whether any of four oil workers kidnapped off the coast of Nigeria are Irish.
An armed group boarded a boat in an oil field in the Niger Delta region and abducted four foreign men working for the oil company, Royal Dutch Shell.
Shell has not said where the hostages come from but they reportedly include one Briton and one American.
No group has claimed responsibility for the kidnapping, but Shell has been in a long-standing dispute with some militant groups based in nearby villages.
Oil companies operating in Nigeria's oil region are regularly the target of kidnappings and the seizure of equipment by armed gangs and youths from the poverty-stricken communities of the area.
