A Chemical Spill recovery team and a road repair team from Tipperary county Council are now at the site of an incident on the (R498) road between Thurles and Nenagh.
Garda in Nenagh say the road will remain closed for several more hours.
A truck carrying chemicals overturned shortly before 7am this morning.
No injuries are reported in the single vehicle incident.
The road is closed on the section between Latteragh and Ballinamona Cross and local diversions are in place.
