Bus Eireann is investigating how a female passenger travelled up to 25km in the baggage compartment of one of its coaches after she was accidentally locked inside.
The middle-aged woman from Co Clare, who does not want to be identified, was travelling to her home in Ballyvaughan from a hospital in Galway where she has been undergoing treatment for cancer.
The journey is about 50km.
However, when the bus arrived in Ballyvaughan, the woman had trouble trying to retrieve her luggage from the baggage compartment.
The small bag is understood to have become hidden behind larger luggage so the woman climbed in to try to retrieve it.