It happened in the early hours of the morning
It happened shortly before 2am on the N25 near Cobh Cross, Tullagreine, Carrigtwohill.
There's no description of the vehicle which failed to remain at the scene, but it's believed it was travelling westbound at the time of the collision.
The road is closed this morning and local diversions are in place.
Gardai are appealing for any road users who travelled in the area between 1:30am - 2:30am to contact Carrigtwohill Garda Station on 021 488 3222 or the Garda Confidential Line on 1800 666 111
