Dead horses dumped at Pentre Meyrick, Cowbridge
Four dead foals have been found dumped among rubbish, says the RSPCA.
They were found in a fly tipping area at Pentre Meyrick near Cowbridge in the Vale of Glamorgan, and have since been removed.
The RSPCA, which is appealing for information, said the horses showed no signs of decomposition, which suggested they had only recently been dumped.
They were not emaciated and there were no visual signs of cause of death.
RSPCA inspector Christine McNeil said: "With no other evidence it is difficult to tell exactly what has happened to these young foals and we are appealing for anyone with information to give us a call.
"Although the horses may well have died from natural causes, or been put to sleep for a legitimate reason, the fact that they are all seemingly healthy young foals does arouse some suspicion as to their cause of death.
"Added to this of course is that dumping horses illegally is not the right thing to do - as a responsible horse owner you must be prepared to pay for your dead animals to be disposed of correctly and responsibly using the appropriate services."
The foals - one black, one grey and two grey and white - were found piled on top of each other.
There was blood on the lower part of one foal's leg and another had blood visible in its mouth.
There were no other horses in the area.
The RSPCA said it had been established that the bodies were not awaiting collection for disposal.
Anyone with information is asked to call the RSPCA's 24-hour helpline on 0300 1234 999.