Forty-seven macaques being smuggled out of Thailand for probable use in Chinese traditional medicine were found in cages on the back of pickup truck in Nakhon Ratchasima.
They were rescued by police and two men were arrested.
Police stopped two pickup trucks around 2am on Monday. One of the pickups was found to be carrying many plastic cages packed with a total of 47 live macaques in small bags. One of the animals was sick.
Police said the driver and his accomplice admitted to transporting the monkeys, but claimed they were unaware the animals were protected wildlife and that they were breaking the law.
The driver said he was paid 17,000 baht to pick up the cages from Ratchaburi and deliver them near the Laos border in Nong Khai province.
Macaques are a protected animal under the Wildlife Conservation and Protection Act.
The macaques were destined for China, officials said, believing they were for use in Chinese traditional medicine.
The rescued animals would be taken to a wildlife centre in Chaiyaphum.
