The puppies are described as "very vocal"

One of the animals died in what the RSPCA is describing as an "horrendous" act of cruelty.

The puppies, which are less than a week old, were discovered by a passer-by and taken to a nearby animal hospital.

RSPCA spokeswoman Ann Parry said it was fortunate that any survived.

Bitch appeal

"It's fairly horrendous," she said.

"These puppies would have died very quickly, especially as it was so cold on that evening.

"They're less than a week old and they need warmth."

The puppies are enjoying the warmth of the animal hospital

The puppies are lively and healthy despite their ordeal, although they are proving to be something of a handful for staff at the RSPCA's animal hospital at Barnes Hill, Weoley Castle, Birmingham.

Manager Janet Voyce said: "It's quite a chore for the nurses to be feeding the puppies every two to three hours.

"They are very demanding and very vocal."

The hospital is appealing for dog owners to come forward with three or four bitches to help care for the animals.