The owners of a three-month-old foal stolen from her mother's side in Kent have warned the horse could die.
Precious, a 2ft (61cm) tall Palomino Shetland pony, was taken from a field in Teston last Wednesday night.
Owner Kayley Cox said the foal needed her mother's milk and the theft had left the older horse pining and running around the field in distress.
Supt Steve Corbishley, of Kent Police, said a number of officers were working on the "extremely serious" theft.
He urged anyone with any information to contact police or Crimestoppers.
The foal is one of a small herd of Shetland ponies kept by Kayley and her mother, Diane Cox.
The foal had not yet been microchipped, but had started to develop some distinguishing marks, including a white blaze down her face and dark hooves.