Officers moved in at the site, in Moo 9, Thepkrasattri, yesterday morning (Mar 5) reportedly after receiving a tip-off on Monday (Mar 3).
Officers arrived to find the warehouse door open and heard construction work inside, said a report of the raid.
Inside the building, four Chinese men were discovered working without permits. They were identified as: Minggui Yang, 33; Yongdong Deng, 45; Zuo Tang, 44; and Xiaohui Xiang (who also used the name Xiaohui Zhang), 37.
Police said the men had been living on site.
All four were taken to Thalang Police Station.
Zuo Tang was charged with working illegally as a construction supervisor, while the other three faced charges of working illegally as construction workers.
All four also were charged with illegally entering and staying in the country.
The four suspects denied all allegations and refused to give any information about their employer, said police.
Police said they were investigating further to identify the employer and have summoned the building owner, named as Peerakarn Wechakul, 51, for questioning.
Peerakarn had leased the building for an interior design business, police reported.
Legal proceedings are ongoing, with police set to expand their investigation into potential employer violations, said the report of the raid.
See also:
Phuket Immigration arrests Chinese couple at Kathu condo
11 arrested as Phuket nominee crackdown continues
Chinese nationals arrested in Phuket for B1bn in illegal business operations
Eight Chinese arrested for working illegally at luxury Phuket villa site