Two men have been arrested on suspicion of poisoning a guard dog at Kirby Misperton in North Yorkshire.
Police were informed that a number of pellets had been thrown over a the fence into the fracking site and eaten by a guard dog yesterday morning.
The dog was sick and collapsed, before it was taken to the vet for treatment.
Officers say several pellets were seized at the site and a caravan parked on Habton Road in Kirby Misperton was searched as part of the investigation.
A 42-year-old man has been arrested on suspicion of administering poison to an animal and causing criminal damage to an animal.
Another 61-year-old man has also been arrested on suspicion of causing criminal damage to animal.
Both men have been released on bail with a condition to stay away from the area around the site gates.