The Limerick road (R503) outside Newport is closed at present as Gardaí deal with a collision.
Motorists are being advised to use alternative routes.
There are no details yet on the accident, and whether or not anybody has been injured.
Meanwhile, a broken down truck is blocking Main Street in Tipperary Town, part of the N24 route.
Delays are building on approach and Gardaí are advising motorists to avoid the town where possible.
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