A climber filmed and stopped a dog attacking sheep in Co Down on Thursday, according to the hill walking organisation Mountaineering Ireland.
The incident took place at Lower Cove in the Mourne Mountains, where the climber ran from the nearby cliffs to rescue the sheep, according to Mountaineering Ireland.
The video shows the few seconds when the climber arrived at the scene before confronting the dog and its owner, the organisation added.
"A family pet, off lead, chased a sheep till the sheep lay down with exhaustion. The family who owned the dog tried to call the dog back, but to no avail," Mountaineering Ireland reported.
The climber then "ran towards the incident while the dog owners walked away".
"The dog was in full attack mode and did not stop until the owner arrived at the scene and put him on a lead," they added.
With summer weather forecast to last through the Easter weekend, the organisation has urged dog owners to keep their pets on a lead in the countryside and to take them on to hill land only when they have the landowner's permission to do so.
"This attack is a stark reminder that family pets can become killers when their instincts kick in," said Mountaineering Ireland on its Facebook page.
"We are sorry that it is necessary to post a message like this at the start of a holiday weekend, but it is with the aim of preventing further dog attacks on sheep."
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