Specialist fire crews are attempting to rescue scores of pigs which fell into a slurry tank.
The incident happened on a farm on the Ballinderry Road at Aghalee, close to the border of Counties Armagh and Antrim.
The alert was raised shortly after 9am this morning (Saturday).
A special rescue team from Newcastle is also taking part in the operation which has been ongoing all day.
Some of the pigs have already been rescued.
It is expected to continue late into the afternoon.
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