The attack is believed to have happened in the area of Fr Cummins Park
Detectives are carrying out searches in Carlow after reports of a sexual assault on a teenage girl.
The 14-year-old appeared on the doorstep of a home in Bagenalstown in the early hours of Tuesday morning claiming she had been assaulted.
The attack is believed to have happened near a bonfire in a local park sometime between 11.30pm on Monday night and 2.15am the next morning.
Speaking to local station KCLR, Superintendent Gerry Redmond says anyone information should come forward.
"We're appealing for witnesses from any persons or people who were at that bonfire, or passed by the bonfire, or passed by the laneways and housing estates near that bonfire at Fr Cummins Park - or were seen in conversation with anybody around that bonfire and that think they may be able to help us with our inquires.
"We're talking about a very serious assault on a young girl."