An elderly man was shocked and puzzled this week when he helped deliver a litter of kittens, and found a Chihuahua puppy in their midst. Pensioner Jia Weinuan, 74, delivered five young from his three-year-old cat Niu Niu, her fifth and largest litter at their home in Xuzhou City, in east China's Jiangsu Province. Weinuan said he personally delivered all five young, but did not notice that a puppy had found its way into the kindle of kittens until several days later. He said that both he and his wife have no idea how the Chihuahua puppy ended up with the cat litter, but added that he is certain that he delivered it himself. Weinuan also ruled out the possibility that Niu Niu mated with a dog, because his cat was placed in the care of his friend, and also because it is impossible for the two species to produce offspring together. The pensioner said: "I sent Niu Niu to my friend's house personally for her to mate. She was put in a cage with a male cat for two days. He would never have put her with a dog." He added: "In all my years, I've never heard of dogs and cats mating. But I am certain that I hand delivered this Chihuahua as there were five babies, and when I looked more closely later there were five babies. This is very confusing. I hope the media reports this and we get some sort of explanation from a scientist."