Chinese tourist 'who plotted bomb attacks with ChatGPT' caught with huge cache of military-grade weapons in Thailand

A Chinese tourist who allegedly plotted bomb attacks in Thailand using ChatGPT was caught with a huge cache of military-grade weapons and videos of him training with the 'Hun Sen Bodyguard Unit'.

Mingchen Sun, 31, and his Taiwanese passenger Ma Yu-hsin, 33, were rescued when their sedan overturned along a slippery road in Chonburi on May 8.

But officers later found military-grade guns and ammunition inside the vehicle while investigating the crash site, triggering a probe of his home at The Maple housing estate in Pattaya.

Officers reportedly discovered a hidden arsenal of Russian landmines, hand grenades, C4 devices, M4 rifles, and tactical vests rigged with bombs.

Police also recovered gas masks, multiple containers of petrol, and 5.56mm M193 cartridges.

The cartridges were labelled 'LOT RTA', indicating they were manufactured by the Royal Thai Army Ammunition Plant for military use.

Sun's mobile phone allegedly contained footage appearing to show him firing weapons and throwing grenades alongside Cambodia's Special Forces Command 911, an elite unit under the Bodyguard Headquarters tasked with protecting Cambodia's top government officials.

He was also found to have consulted ChatGPT about sabotage and C4 explosives.

The home was cordoned off as bomb disposal officers carried out further investigations.

Sun was charged with illegal possession of firearms, ammunition, explosives and military ordnance, and carrying firearms in a public area without a permit and without reasonable necessity. He reportedly admitted to all charges.

Authorities said they are tracing the source of the war weapons and probing potential links to terror groups.

Police General Kittirat Panpetch, Commissioner-General of the Royal Thai Police, said: 'Although we have currently found no evidence linking the case to terrorism or espionage, we will continue expanding the investigation to prevent this type of incident from occurring in the future.

'This is part of a proactive security operation that has been underway since early 2026 to scan and monitor threats nationwide.

'Regarding the video showing the suspect training with alleged Cambodian soldiers, the investigation is still ongoing whether the training was intended to be used for sabotage in Thailand or linked to intelligence sources.

'Concerning the semi-automatic pistol found on the suspect after the accident, it was determined to belong to a police officer from Sai Mai Police Station. It was sold within the police force and through a chain of sales until it came into the possession of this Chinese suspect.

'The police officer is being investigated. It must be acknowledged that police officers are currently burdened and facing financial difficulties, leading them to sell firearms. These firearms were purchased legally and were not police service weapons. If it is found that the officer himself is guilty, decisive action will be taken.'

Sun claimed he suffered depression and allegedly plotted a suicide bombing to end his life.

However, officials said they doubt his explanation as he allegedly had searches on his phone related to terrorist attacks, C4 explosives, and car bombs.

Police seized from Sun's car a Glock 26 handgun with two magazines, 10 rounds of 9mm ammunition, and a concealed-carry holster.

They also recovered from his home two M16 rifles, 10 M16 magazines, 791 rounds of 5.56mm ammunition, 3.7kg of C4 explosives, four Russian-made POMZ-2 anti-personnel mines, six hand grenades of various types, seven electric detonators, POMZ-2 fuse assemblies and safety pins, and two remote-control transmitter and receiver sets.

Police Major General Pongphan Wongmaneethet, commander of Chonburi Provincial Police, has declined to reveal further details, saying it could compromise the ongoing investigation.

However, he said officials have not ruled out terrorism as a motive.

He said: 'Officers are continuing their investigation and have linked several individuals to the possession and supply of weapons to the suspect.

'Regarding the explosives, investigators are gathering evidence and technical data while examining further connections, including people who may be involved both inside and outside government agencies.

'We have not ruled out sabotage, terrorism, or links to organisations affecting national security. Officers are carrying out an in-depth investigation, including forensic examinations and analysis of the behaviour of everyone involved.

'Despite reports that the suspect suffers from mental illness or depression, this does not exempt him from prosecution. The possession of dangerous weapons and explosives poses a serious threat to national security and public safety, particularly in Chonburi province, which is a major tourist destination.'

Security agencies have been assigned to investigate Sun's background and criminal history, international travel records, his occupation and associates, the origin of the weapons and how they were obtained, and communications and financial transactions linked to his mobile phone and bank accounts.

Authorities said Sun had been living at the housing estate for around two years. He first entered Thailand in 2020 on a tourist visa and had travelled in and out of the country frequently.

He was reportedly married to a Thai woman named Jantima in 2022, but divorced three years later. Police said she is also under investigation.

Sun last entered Thailand on January 27, using a re-entry permit under a long-term visa valid for five years.

He possessed both Chinese and Cambodian visas, along with a pink ID card for long-term foreign residents in Thailand.

He was registered as a resident of Khlong Sam Wa district in Bangkok after he reportedly moved from Chiang Mai in November 2023.

Sun's neighbour told officers: 'He was normally friendly and approachable. However, we were terrified to learn that he was storing dangerous materials, especially C4 explosives. If the bomb had detonated, the entire village would have suffered.'

Police on May 9 detained shooting range instructor Kachen Sianglam and Thai navy officer Methee Narom over alleged links to the weapons supply chain.

Kachen allegedly helped procure the firearms before passing them on to the Chinese suspect.

Investigators also found that a M4 rifles and a C4 grenade were allegedly purchased from Petty Officer 1st Class Methee Narom, a member of the Royal Thai Navy, for 200,000 baht.

Police Major General Thitawat Suriyachai, Deputy Commander of Provincial Police Region 2, said investigators, immigration police, and forensic officers were working together to expedite the probe into the origin of the weapons, the suspect's financial transactions, and whether others were involved.

He said: 'We ask members of the public who may have information about the suspect or related individuals to report it to authorities immediately. We are prepared to provide witness protection and will examine all information received as part of the investigation.'