Thai military releases aerial evidence of Cambodian military buildup before border clash
The images show that, for over 70 years, neither side had settled or actively used the disputed area — contradicting Cambodian claims of long-standing occupation.
The Royal Thai Armed Forces (RTARF) on Tuesday released a set of aerial maps and images comparing past and recent military activity in the disputed Chong Bok border area of Ubon Ratchathani Province. The release follows the May 28 clash between Thai and Cambodian troops.
According to RTARF spokesman Maj Gen Withai Laithomya, the aerial data documents changes in terrain and movement from as far back as 1954, with updates from 1977, 1984, 1996, 2003, 2010, and 2018. The images show that, for over 70 years, neither side had settled or actively used the disputed area — contradicting Cambodian claims of long-standing occupation.
The red boundary line on the map reflects the territorial line recognised by Thailand, separating it from Cambodia and Laos. The clash zone lies on what Thailand identifies as its side of the border, said Withai.
He stated that comparative aerial images from 2020 to April 2025 show increased Cambodian military activity. In just one month — from April to May 24, 2025, just days before the May 28 clash — the images clearly show the construction of military trenches, which are suspected to serve as defensive and logistical routes.
Additional findings include:
- A cut-down Phaya Satabann tree obstructing Thai patrol routes — an act traced back to April 2025.
- At Hill 574, images from April 20, 2025, showed no disturbances. However, one month later, the area had been cleared with heavy machinery, and new trenches and supply routes had been established.
- At Hill 641, no military presence was visible in 2020 or February 2025, but by May 24, Cambodia had built a military base, upgraded trenches into firing positions, and converted dirt roads into 4–6 metre-wide concrete roads.
- At Hill 475, aerial images from 2004, 2020, and early 2025 showed no activity. But by May 24, Cambodia had dug a long trench and cleared the area, creating what appears to be a tactical trench network.
Withai said these trench constructions are seen as military signals of intent and constitute a violation of the 2000 Memorandum of Understanding (MOU) between Thailand and Cambodia. The MOU states that undemarcated areas must be jointly used for patrols and activities, without altering the landscape or creating military installations.
Thailand has issued formal protests demanding Cambodia cease such activities and return to the previously agreed conditions, but no compliance has been observed, Withai said.
