Two adult cats and three 10-week-old kittens were found abandoned in a cardboard box, alongside a note pleading for them to be re-homed for Christmas.
The stricken cats were found outside Luton and Dunstable University Hospital in Lewsey Road at around 8am on Monday.
A member of staff at hospital clinic contacted the RSPCA after she spotted them, before a rescue was launched.
The felines were discovered in a loosely taped-up box with a note on it which read: “Need a home. Merry Xmas - please help them.”
The family of cats include two-year-old tabby and white cat Elle, who is believed to be the mum; one-year-old tabby female Dee, who is believed to be her slightly younger daughter.
Two black and white and one tabby kittens named Amber, Penny and Lance were also found dumped in the box.
Inspector Melanie Fisher, who rescued the family, said: “These cats were abandoned in a box outside the hospital early on Monday morning. Thankfully they are all in good condition and have obviously been well looked after previously.
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“They are socialised and nice and friendly but sadly someone has left them behind.
“We understand that people’s circumstances can change which might mean they can no longer care for their pets but dumping an animal is never the answer.
“Luckily, these cats were found by a kind member of the public and are now being cared for by the RSPCA”
Anyone with information is asked to contact the RSPCA on 0300 123 8018.
On Christmas Day in 2018, the charity received 934 calls to its cruelty line.
It was the highest number of calls received for five years - almost a third more than in 2017.