On 7 December 2025 at around 14:15 afternoon, Cambodia's Ministry of National Defense stated that Thai troops had opened fire with small arms, B-40 rockets, and 60 mm mortars at a Cambodian position in Prolean Thmor area of Choam Khsant District, Preah Vihear Province. Cambodia stated that its troops immediately contacted their Thai counterparts to halt the attack, did not return fire, and that the shooting ceased by 14:32.
On Thailand's side, the Ministry of Defense stated that Cambodian forces opened fire at around 14:15 at an area around Phu Pha Lek-Phlan Hin Paet Kon of Sisaket province while Thai soldiers were carrying out a mission to improve the route from Phu Pha Lek to Phieng Fa Checkpoint. Two Thai soldiers were injured, one shot in the leg and another shot in the chest area of his body armor. Thailand stated that Cambodian forces also fired a recoilless gun into Thai territory, prompting Thai forces to return fire in accordance with the rules of engagement and international principles of proportionality.
After 7 December, the situation started to escalate.
On the morning of 8 December, fighting erupted across the border. The 2nd Army Area of the Royal Thai Army announced that the RTAF had launched an air strike campaign along the border with Cambodia in retaliation to clashes that killed one Thai soldier in Ubon Ratchathani province. The RTA also claimed that the RCA launched BM-21 rockets against Thai civilians.
At 14:30 Thailand set a ultimatum for a ceasefire at 18:00 or Thailand will use its full military strength. Thailand said it will continue using military action against Cambodia. Cambodia denied the claims that clashes resulted in the death of a Thai soldier. Cambodian information minister Neth Pheaktra later told Agence France-Presse that Thai attacks killed at least four Cambodian civilians in Oddar Meanchey and Preah Vihear and that 10 others were also wounded.
Fighting intensified on 9 December after the ultimatum. That same day, the RTN stated that "up to 80%" of Cambodian positions including weapon and supply storage were destroyed by the Royal Thai Marine Corps (RTMC) during the operation around the "Three House" casino complex near the border of Trat province, while the RTMC suffered no casualty.
ทร. ยันนาวิกโยธินปลอดภัย พื้นที่บ้าน 3 หลัง ฐานกัมพูชากว่า 80% ถูกทำลายไปแล้ว
In this video we see the launch of multiple rockets, it is stated that these rockets are fired Cambodian BM-21 launchers. These BM-21s are not visible on the video, we only see some Thai Scorpion light tanks and M113s passing by.
In this one we can see a BM-21 on a road, and the attack by Thai F-16s on a building complex used for online gambling. According to Thailand these buildings are now used to operate UAVs.