Gardaí and emergency services are currently at the scene of this single-car collision, which occurred at around 1.15 this morning, on the N80 in Rathoe.
The driver and a passenger, both men aged in their 20s, were pronounced dead at the scene.
Two other passengers of the car, a man and woman also in their 20s, have been taken to St. Luke's General Hospital in Kilkenny with serious but non-life threatening injuries.
The road is currently closed and will remain closed for several hours while Gardaí examines the scene. Local diversions are in place.
Gardaí are appealing for any witnesses to come forward.
It is understood the vehicle involved in this collision was travelling from Mount Leinster to Carlow town via Fenagh. Any road users who may have camera footage (including dash-cam) and were travelling along this route, or who were on the N80 at Leagh between midnight and 1.15 am are asked to make this footage available to Gardaí.
Anyone with any information is asked to contact Carlow Garda Station on 059 913 6620, the Garda Confidential Line 1800 666 111, or any Garda station.
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