According to the police, the men were caught illegally entering the accident site during last week's powerful earthquake in Myanmar and removing over 30 files from there.
According to Thai news portal The Nation, the men were caught illegally entering the area of a high-rise building that collapsed during the earthquake and removing more than 30 files from the location.
The building, the only high-rise in Bangkok to collapse due to the tremors from the Myanmar earthquake, was part of a Chinese-backed construction project. It crumbled within seconds after the 7.7 magnitude quake hit, leaving behind rubble and trapping dozens of people beneath it.
The collapse has raised significant concerns about the handling of the disaster site and the motives behind the individuals' actions.
Police Major General Nopasin Poolswat confirmed to the local media that the four Chinese nationals had been caught removing 32 files of documents from the collapsed State Audit Office (SAO) building.
The Bangkok authorities designated the site as a restricted area where no one was allowed to enter without authorisation. However, the police later received information about some individuals removing documents from the site.
During the police probe, it was revealed that one of the men had a valid work permit and claimed he was the project manager for a building construction project.
Three other men were later found, and the stolen documents were recovered, including blueprints and various other paperwork related to the building's construction.
Meanwhile, the detained individuals explained to authorities that they were subcontractors working for the construction firm involved in the project.