Customs officers in southern China rescued 806 Siamese crocodiles and more than 2,700 crab-eating macaques in separate raids on smuggling gangs operating in the region, according to state media. At least 35 people were detained in the strikes, which also recovered about 100,000 dried seahorses, China News Service reported on Thursday, citing the customs authority in Nanning, capital of the Guangxi Zhuang autonomous region. Siamese crocodiles and seahorses are protected under the Convention on International Trade in Endangered Species of Wild Fauna and Flora, while crab-eating macaques have grade II protection in China . The crocodiles were discovered during a raid last month in the coastal city of Fangchenggang. They had been packed into 158 wooden boxes and their mouths had been bound with duct tape, the report said. Officers involved said the passive behaviour of the reptiles suggested they had been kept in cramped conditions for some time. They were later transferred to an animal protection facility. A total of 16 people, 14 of them Vietnamese who had entered China illegally, were detained, the report said. In a separate raid, customs officers rescued 2,735 crab-eating macaques that had been smuggled into Guangxi from Vietnam , the report said. The strike, which resulted in 17 people being detained, came after a months-long investigation sparked by the discovery of 70 monkeys in the back of a truck during a routine vehicle inspection. The animals were bound for a company in Wuzhou, in the east of Guangxi, that planned to sell them on for use in vivisection laboratories, the report said. The dried seahorses, which are commonly used in traditional Chinese medicine, were seized in separate raids in Guangxi and neighbouring Guangdong province. The remains of about 35,000 animals were recovered in the first strike on a flat in Dongxing, a small city on the China-Vietnam border, which also saw an undisclosed number of people being detained, the report said. Information provided by the suspects led the authorities to a second location in Guangdong, where a further 65,000 dried seahorses were recovered and two people were apprehended. The customs authority in Nanning said there had been a sharp increase in the smuggling of protected animal species in the region in recent months but that it would continue to crack down on it.