An investigation is under way after an Air Corps helicopter had to make a "hard landing" in a field in Co Tipperary while on an emergency call out.

It is understood the helicopter may have hit a power line and was forced to land a couple of kilometres outside Borrisoleigh on the main Nenagh road shortly after 2pm.

The helicopter was on an air ambulance mission to pick up a patient in Borrisoleigh at the time. There were three people on board, but there were no injuries.

The patient was subsequently transferred by ambulance to the Mid Western Regional Hospital Limerick.

A statement from the Department of Defence says the Air Accident Investigation Unit in the Department of Transport, Tourism and Sport has been informed of the incident.

It added that the extent of damage to the helicopter is yet to be determined.

Contingency plans are being put in place to resume the Emergency Aeromedical Service as soon as possible.