It happened on the M7 yesterday.
Gardaí are investigating an incident of criminal damage on the M7 in Laois.
A rock was thrown at the windscreen of a vehicle on the motorway near Borris in Ossory on Sunday.
The car's window was heavily damaged in the incident.
Gardaí are appealing for witness with camera or dascham footage to make it available to them.
Anyone with any information is being asked to contact Roscrea Garda Station.