Using pets as sacrifices for Khru Kai Kaeo, represented by a sculpture at a shrine in Bangkok, is against the law, the Watchdog Thailand Foundation has warned.

The warning came on the back of growing concerns from pet lovers shocked by the news of worshippers obtaining cats, dogs and rabbits and killing them.

In a Facebook post, the foundation said believers must think twice before they consider harming pets and using them as sacrifices to the half-human, half-mythical bird sculpture installed at the Ganesha shrine near Huai Khwang intersection.

Intentionally harming animals was against the animal cruelty law, which carries a heavy penalty.

The sculpture made headlines when it was taken on the back of a truck from a studio in Ratchaburi to the Huai Khwang shrine on the morning of Aug 9. The truck was stuck at a pedestrian bridge, stopping traffic on Ratchadaphisek Road for about two hours.

The sculpture's unusual appearance sparked debate about what it represents. According to some believers, Khru Kai Kaeo was the teacher of a former king of the Khmer Empire.

One history scholar, however, said he has never heard of this teacher.

Although it is not against the law to worship a statue, the animal sacrifice craze shows how insecure many Thai people have become in their desperate search for spiritual support, the scholar said.