The defenceless animals had been put inside a plastic bag with bricks attached and chucked into the water at Chapel Strand.
A local man out for a walk yesterday found the bag and was sickened when he opened it to find the dead kittens inside.
“They were found next to the pier,” said the shocked local.
“The tide was out at the time. It was just awful.
“There is just no need for this anymore. There are plenty of animal charities out there who could have found them new homes.”
The pictures of the dead kittens are appalling. But one of them had the same markings and colour as the one featured in our picture. The other was black and white.
The incident follows others in recent weeks.
Several puppies were found abandoned – though thankfully still alive – at Rathmullan beach.
Donegal Pet Rescue is trying to find new homes for them.