Two ponies have gone missing from Barwell Stables in Chessington.
A piebold, black and white, and a skewbold, brown and white, both disappeared in the early hours of Monday and riders said they may have been stolen.
Owner Emma Shaw said she has had the piebold pony for almost 12 years.
She said she did not want the thieves to know the names of the horses.
There was a reward for their safe return, she added.
Ethel McGrath, deputy manager at the William Bourne pub, formerly the Bonesgate, said two ponies had appeared on CCTV being led by two people at about 12.25am on Monday.
Anyone with information is asked to call 07979 126061.