The provincial police investigation agency said on Monday that the suspects were arrested in connection with repeated thefts of electrical equipment at the tourist site.
The six suspects, aged between 25 and 39, are from the provinces of Nghe An, Thanh Hoa and Thai Nguyen.
The investigation began after authorities discovered repeated thefts of street lighting cables, causing substantial property damage and disrupting security and tourism activities.
Police said the group carried out the thefts at night, cutting street lighting cables, stripping out the copper cores and selling them to scrap dealers to fund drug use and personal expenses.
Investigators said the group committed more than 10 thefts between early May and their arrests, stealing more than 1,200 metres of electrical cable and causing significant losses to the management board of Tuyen Lam National Tourist Area.
In early May, the management board reported that thieves had stolen components from the lighting system at two locations, causing losses of about VND 60 million (around USD 2,280).
Authorities said similar thefts were also reported in November and December 2025, when transformers, power cables and other electrical equipment were stolen despite increased patrols and the installation of surveillance cameras.