The RSPCA say the cats are no more than 10 days old.
The RSPCA is appealing for information after four kittens were found abandoned in a park in Bradford.
The kittens, two tabby and two black, were found in the park off Salt Street in Manningham by a member of the public at about 3pm on Monday. The passerby spotted an igloo style cat bed inside a cardboard crate and contacted the RSPCA.
Animal Collection Officer (ACO) Tina Hallas collected the tiny kittens who are no more than 10 days old.
She said: "The kittens were lucky that a passerby spotted the cat bed and realised there were kittens meowing inside otherwise they may not have been found in time.
"It was about four degrees yesterday which although cold is a lot warmer than the snowy weather we've had recently. Thankfully the Beast from the East had moved on or it could have been a different story for these newborn kittens. It's still early days but so far they are feeding and doing well.
"There is never an excuse to abandon an animal like this and there are plenty of other options for someone who can no longer cope or look after their pets.
"I took the kittens home that first night so that someone could be on hand to feed them round the clock. They are more time consuming than a baby as they need feeds every two to three hours so it was a sleepless night!
"It's not the first time I have taken my work home with me! Last year, I had three different litters of kittens but thankfully the RSPCA Leeds and Wakefield branch had a volunteer fosterer who could take them in and is looking after them now."
ACO Hallas is now appealing for anyone with information about how these kittens came to be abandoned to contact the RSPCA in strictest confidence on 0300 123 8018.