The bodies of 40 tiger cubs have been found in a freezer at Thailand’s famous Tiger Temple, many seem to be just a few days old when they died. The discovery was made when police and government wildlife officials raided the temple in an operation to remove the 137 live tigers that are kept there.

The Buddhist Tiger Temple, located west of Bangkok, is a popular destination for tourists in Thailand because it allows visitors to get up and close with the animals, petting and posing for photos with them.

Many animal rights activists and organizations accuse the temple of running an illegal tiger breeding and trading program out of the temple, the discovery of the frozen tiger cubs has been pointed to as proof of this. PETA has called the temple hell for the animals.

In a statement on its Facebook page the temple denied these allegations, saying that cubs were kept as proof that they were not being sold into the animal parts trade, something they say authorities were aware they were doing.

A vet who was working with the temple in 2010 reportedly changed their policy of cremating dead cubs, instead opting for freezing them as proof that they died of natural causes and were not being dismembered and sold.

An Englishmen who had volunteered with the temple told the BBC that some of the bodies had been frozen for at least 5 years, adding that if the intent was to sell the animals it would be irregular to keep them for so long.

The operation to remove the tigers from the temple has been going on for years, its culmination began on Monday and involves at least a thousand police officers. While many of the tigers have already been removed, the process is likely to continue throughout the week.