Police say the Irish visitors were vacationing in the province on May 31, and were on the Duffey Lake Road, driving from Whistler to Sun Peaks, when they arrived at the scene of a crash that killed three people.
An RCMP release says the three tourists, an older, married couple and a female relative, stopped their black Jeep Cherokee to help and officers believe the three may have vital information.
Two cyclists died when an oncoming vehicle veered across the centreline and smashed into them on a rural section of highway, 25 kilometres north of Pemberton.
A passenger in the vehicle was also killed, but the driver survived his injuries.
Cpl. Ronda Rempel says the force has dedicated a significant amount of resources to the ongoing probe and anyone who has information about the Irish tourists should contact police.