Three lambs died and a number of others were injured after being attacked by a large dog in a village near Kettering.
The incident took place between 7.30am and 8am yesterday (Sunday) in a field near St Johns Lane in Cranford.
Three lambs subsequently died, five are being treated and others sustained minor injuries.
Police have received reports of animals being chased and attacked by a large dog in the field and would like to speak to anyone who may have witnessed this incident or who may have any information regarding it.
Officers are reminding dog owners that it is an offence to have a dog off a lead or not under close control in a field of sheep, or to let their dog chase or attack livestock.
Witnesses or anyone with information about this incident can contact police on 101 or Crimestoppers anonymously on 0800 555111.