Three illegal Chinese immigrants hiding in a border village and waiting to be taken to work for phone-scam and online gambling gangs were arrested during police raids in Ubon Ratchathani province.
The Thai man who sheltered them was also arrested.
Teams of police, soldiers and local officials raided five border villages in Khemmarat and Pho Sai districts on Monday afternoon, acting on information that Chinese men who entered the country illegally were hiding there.
The operation was led by Ubon Ratchathani immigration chief Pol Col Chatchai Samniang.
Three Chinese men were arrested in Khemmarat district - Jiang Jiang, 33, Cheng Mao Sheng, 19 and Zao Hui Fan, 22 - along with Thai villager Phornphana Buddaphan, 46. The Chinese were charged with illegal entry, and Mr Phornphana with hiding them.
The trio were awaiting transportation to towns in the North and the East to work for a phone call gang and an online gambling gang based in a neigbhouring country, police said. A van used for smuggling was also seized.
During questioning, Mr Phornphana said he had picked up the three Chinese after smugglers brought them in from Laos. The three men were to stay at his house for one night and then a vehicle would arrive and take them to their destination. He had been paid 4,000 baht per head and had done this three times previously.
Pol Col Chatchai said the arrests were in line with the policy implemented by national police chief Pol Gen Damrongsak Kittiprapas and deputy natonal police chief Pol Gen Surachate Hakarn, to crack down on illegal migrants along the northeastern border.
Chinese nationals were illegally entering the country through this area to work for and run illegal businesses, the provincial immigration police chief said.
The investigation was being extended to arrest other Thais involved in the smuggling of Chinese illegals.