Wildlife officials in Thailand have begun removing some of the 137 tigers held at a Buddhist temple following accusations that monks were involved in illegal breeding and trafficking of the animals.

The director of Thailand's Wildlife Conservation Office, Teunjai Noochdumrong, said three tigers were tranquilized and transported Monday in an operation involving about 1,000 state personnel that is expected to continue for a week.

The animals will be taken to two government animal centers elsewhere in Thailand.

The temple, a popular money-earning tourist attraction in the western province of Kanchanaburi, has been criticized by animal rights activists because of allegations it is not properly set up to care for the animals and flouted regulations restricting their trade.