The Deputy Commissioner of Region 2 revealed that in the case of "A-Tee C4," a Chinese man found possessing military weapons, including M4 assault rifles linked to five individuals—three civilians and two military personnel—authorities are urgently examining financial trails and mobile phone data to expand the investigation. So far, no evidence links the case to security threats. Detailed inquiries are underway to determine whether this is merely a hobbyist collecting and practicing shooting or if there is a concealed objective.
On 11 May 2026 in Chonburi province, reporters provided updates on the "A-Tee C4" case involving 31-year-old Chinese national Ming Chen Sun, who was found in possession of military firearms. Pol. Maj. Gen. Chokchai Ngamwong, Deputy Commissioner of Region 2, disclosed after a case follow-up meeting at Nong Prue Police Station, under orders from the Region 2 Police Commander, that investigators have charged Ming Chen Sun with three offenses: possessing firearms that cannot be licensed by the registrar, carrying firearms in public without justifiable cause, and possessing military equipment without authorization. He has been detained and sent for court custody at Pattaya Provincial Court.
Regarding 33-year-old Taiwanese national Yu Hsin Ma, who was present at the scene, no evidence currently links her to charges, but authorities continue to detain and question her for further investigation. Meanwhile, the Immigration Bureau has revoked the visas of both individuals.
Two M4 rifles seized from a residence in Huay Yai subdistrict, Bang Lamung district, Chonburi province, were found by investigators to be connected to five people: three civilians and two soldiers. It is believed these weapons were supplied to Ming Chen Sun within the Sattahip Police Station area. All five were summoned to acknowledge charges related to jointly distributing firearms that cannot be licensed by the registrar. Although all accused denied the charges, police maintain there is sufficient evidence to proceed with prosecution before releasing them on bail. The two soldiers have been taken into custody by their superiors for disciplinary action.
Regarding the Glock 26 pistol found inside a vehicle, police have recently traced its origin and linked it to a police officer. Coordination with Metropolitan Police is ongoing to investigate and prosecute. Meanwhile, one more M4 rifle is still under examination due to lacking serial numbers and is a firearm type that cannot be licensed.
The Deputy Commissioner of Region 2 further stated that investigations reveal Ming Chen Sun has a hobby of collecting and practicing shooting firearms, with records showing multiple visits to shooting ranges. However, police are conducting thorough checks to determine if he is merely a collector or has other hidden aims. Efforts are being accelerated to analyze mobile phone data, financial transactions, and technical information to expand the probe and identify additional involved parties.
So far, authorities have found no evidence linking Ming Chen Sun to plans threatening Thailand's national security, nor connections to government agencies, despite information indicating illicit arms trading since late last year.
On the matter of Ming Chen Sun's nationality, police stated that evidence links him to China, the Dominican Republic, and South Korea, as well as possessing a Thai pink identity card. No proof currently shows Cambodian citizenship. Further detailed verification is underway.
Regarding the white Toyota Altis sedan with Chonburi license plate ฉง 2305, which the suspect was driving during a roadside accident near the Huay Yai railway, police conducted a thorough background check. The vehicle was previously a green-yellow taxi with a yellow plate. After decommissioning, it was sold and re-registered with a white plate around 2021. By late 2025, it was sold again and re-registered under a new owner. Police are investigating the seller's identity. The car has been modified as a lowered racing vehicle, equipped with expensive Brembo brakes costing up to 160,000 baht, alloy wheels, a turbocharged engine, and an intercooler pipe, resembling a track racing car.