Fortunately a nearby worker heard noises in the skip which was on land at the Anglian Home Improvements centre, in Teal Farm Park, Washington.
Now the RSPCA has appealed for help to find the people responsible.
Inspector Trevor Walker, who had to climb inside the rubbish strewn skip to rescue the frightened felines, said there was no doubt they had been placed in the skip deliberately: “It was impossible for these cats to have made their way into this skip themselves as they are so high,” he said.
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"Once I was inside to rescue them I also noted a cat bed - which suggests someone has deliberately discarded them in such a callous way.
“Both cats were terrified from their ordeal and were so scared to come to me initially. They are now in RSPCA care where they will remain until they are ready to be rehomed.
“I am now appealing for information to find the person responsible for dumping these pets like rubbish. They were very lucky to survive as glass items are disposed of in the skip daily and it was because the company was closed over Christmas that this had not happened.
“They could so easily have suffocated under the debris, risked serious injuries and could have suffered a lingering death from starvation.”
Trevor is now hoping someone may have information as to who the two cats - which were not microchipped - belonged to. They were found on Wednesday, December 29.
One is a white and grey tabby male adult which staff at RSPCA Fell Edge Animal Centre have named Simon and the other is a black tabby female, aged about 12 months, staff have named Sox.
Some household waste was also found in the skip which it is hoped may provide clues and Insp Walker will be checking CCTV footage in the area.
Anyone with information on nhow the cats came t be in the skip should contact the RSPCA appeals line number on 0300 123 8018.
The RSPCA relies entirely on public support. To donate, visit www.rspca.org.uk/rescuexmas