More than 80 sheep died after a truck rolled over on Guyra Road on Tuesday afternoon.
The accident took place 1 km west of Guyra (towards Tingha) at about 12.30pm on Tuesday.
The Tamworth prime mover was towing a Stockmaster stock crate carrying 430-odd sheep to Kempsey.
Police said the driver was trying to turn left on a bend on the Guyra Road when the trailer being towed overbalanced and rolled over.
The driver, a 30-year-old man from the Tamworth suburb of Westdale, was able to free himself, and was uninjured.
The accident resulted in more than 80 sheep having to be put down.
Road and maritime inspectors, rural firefighters and police were called to the scene.
New England police are still investigating the circumstances surrounding the incident. If the driver is determined to be at fault, he may receive an infringement notice.