The collision, which involved two motorcycles, occurred on Thursday afternoon.
Gardaí are continuing to appeal for information in relation to a serious road traffic collision in Prosperous.
Two people were brought to hospital following the incident on Thursday 13th July at approximately 2.10pm.
The collision, which involved two motorcycles, occurred at Healys Bridge between Prosperous and Kilmeague.
Two motorcyclists collided with the bridge. The male drivers of both motorcycles were taken to Tallaght University Hospital with serious injuries.
Gardaí are appealing to any person who may have information in relation to this collision to contact them.
Any road users who were travelling in the vicinity of Prosperous and Kilmeague on Thursday afternoon, between 1.45pm and 2.30pm, and who may have camera footage (including dash cam) is asked to make this available to investigating Gardaí.
Anyone with information in relation to this incident can contact Naas Garda Station on 045 884 300, the Garda Confidential Line on 1800 666 111, or any Garda station.