Thai troops uncover a secret tunnel network at a Cambodian base near the disputed border — packed with ammo stores, bunk areas and reinforced shelters — as commanders say vigilance is the watchword despite latest reports saying the frontier remains stable.
The Thai-Cambodian ceasefire is holding, with military sources reporting a calm situation on Thursday. However, the Royal Thai Army has revealed the discovery of advanced tunnels in captured Cambodian positions, highlighting the determination of Cambodian forces. The tunnels were carved deep into rock and contained storage and waiting areas. On Thursday, Thailand’s 2nd Army reported that although the border remains peaceful, Cambodian troops are repairing facilities and strengthening fortifications.
Thai soldiers have reported the discovery of a large underground tunnel network at a Cambodian military base. Meanwhile, the find came during clearance operations near a disputed border zone. The discovery then became public on January 1, 2026.
A video on the Facebook page “Army Military Force” showed soldiers entering the site. The post explained that the tunnels stretched for dozens of meters beneath the base. Moreover, the passageways had been dug deep into rock layers.
Inside, soldiers found storage rooms for ammunition. There were also reinforced shelters. In addition, enclosed camping areas for troops were identified as well. Overall, the system appeared complex and extensive. Consequently, Thai personnel described the discovery as astonishing.
Briefing says tunnels were long-term works while overall border calm but still a need for vigilance
However, the tunnels did not appear temporary. Instead, they showed signs of structured excavation. The rock surfaces were cut and drilled. In addition, spaces were divided into specific rooms. Storage areas looked organised.
Shelters appeared designed to withstand impact. Likewise, living quarters were closed off from the outer areas. Therefore, the discovery suggested long-term preparation. Thai officers continued to catalogue the site. Consequently, evidence was recorded and secured.
Meanwhile, the 2nd Army Region issued a formal briefing on the border situation. The report was delivered at 9:30 a.m. on January 1. It summarised conditions along the Thai-Cambodian border on December 31, 2025.
Commanders described the overall situation as calm. However, they added that it was not yet reassuring. No unusual incidents were detected across several sectors. Nevertheless, surveillance operations remained active. Thai officials stressed continued monitoring.
Calm conditions reported across Ubon, Sisaket, Surin and Buriram sectors with ongoing monitoring
The border sector between Ubon Ratchathani and Sisaket provinces remained quiet. Chong Bok and Chong An Ma showed no significant troop movement. There were no new developments reported there.
In Sisaket province, several locations remained stable. These included Chong Sam Tae, Don Tual, Phu Phi, Sattasom, Phnom Prasitthiso, and Chong Ta Thao. The Preah Vihear temple area remained calm as well. Additionally, Pha Mor E Daeng and Huai Ta Maria saw no clashes. Cambodian troops continued to observe Thai activity. They monitored road works and troop movements.
Further west, the Surin and Buriram border zone remained stable. The area around Prasat Ta Kwai showed no new activity. Hill 350 also remained unchanged. Prasat Ta Muen Thom in Surin province saw no escalation.
Moreover, in Buriram province, several crossings remained quiet. These included Chong Chom, Chong Rayi, Plod Tang, and Chong Sai Takoo. Patrols continued routine observation.
Cambodian forces reinforce rear positions and supply lines while the Thai army reports border calm
However, Cambodian troops continued defensive work in rear areas. They modified positions and strengthened cover. Power and signal lines were repaired. Sandbags were filled and placed. Trenches were dug for protection.
Support systems were installed at several points. Weapons and ammunition were moved forward. Survival supplies were transported. Motorcycles carried much of the equipment. These activities suggested continued preparation work.
Throughout the reporting period, there were no heavy armed clashes. No cross-border incursions were confirmed. However, Cambodian forces maintained a high alert status. They continued to reinforce positions. Information controls were enforced. Meanwhile, Thai units reported firm control of their side of the border. Commanders stated that the situation remained calm and orderly.
Hun Sen celebrates return of 18 detainees after ceasefire as Thai officers warn of third offensive
At the same time, a political development unfolded in Cambodia. De facto leader and strongman Hun Sen marked New Year’s Day by celebrating the return of 18 detainees. These detainees had been held in Thailand as prisoners of war since July 2025.
They were returned to Cambodian custody on New Year’s Eve. The handover followed a review by the National Security Council. The council concluded that a provisional 72-hour ceasefire had held. The ceasefire took effect on December 27. The transfer proceeded after confirmation of its stability.
Cambodian officials described the release as a forward step. The development came during a period of reduced tension. However, Thai military commanders issued continued warnings. They stated that Cambodia may be readying for a third offensive. They cited ongoing reinforcement and position adjustments. Monitoring, therefore, continued across the frontier.
Meanwhile, Thai soldiers continued reporting their reaction to the tunnel discovery. The network appeared designed to store ammunition safely. It also provided shelters for troops. Camping zones were protected within the underground system.
Thai army says border calm as Cambodia repairs infrastructure and strengthens lines
The tunnels extended for dozens of meters. They had been drilled and dug into rock formations. The scale indicated planning and engineering effort. Thai personnel documented each section carefully. The system appeared to support continued operational use.
Additionally, Thai officers underlined that the overall border situation remained calm. However, they warned against complacency. Forces stayed on alert. Control posts maintained observation. Patrols recorded activity along key corridors. No heavy fighting took place. No violations of the ceasefire were confirmed.
Earlier, the 2nd Army Region stated that Thailand maintained control of the situation. They confirmed that surveillance would continue. Commanders described the border as calm but not yet secure.
Cambodian forces continued infrastructure repairs. They strengthened defensive lines. They transported supplies to forward positions. Trenches and sandbag positions were expanded.
Underground tunnel network seen as a key development as engineering inspections continue
Meanwhile, the political symbolism of the prisoner release remained significant. Hun Sen appeared publicly to mark the event. The 18 detainees had been held for approximately five months. The return followed the recent ceasefire.
The truce lasted 72 hours before the transfer. It went into effect on December 27. Cambodian authorities said the National Security Council believed the ceasefire had held.
Therefore, the beginning of the new year opened with a mixed picture. There was calm on the ground. There was a prisoner release at the political level. However, there were also tunnel discoveries and troop reinforcement. Thai forces continued high-level monitoring. Cambodian units continued defensive works.
The border, in the meantime, remains quiet. Surveillance also remains constant. Military briefings continued daily. Commanders described stability. However, they particularly stressed vigilance.
Discovery of underground tunnels reveals Cambodian defences, including ammunition storage
The discovery of the underground network remained the most striking development. Certainly, it showed the extent of defensive structures near disputed zones. It revealed ammunition storage and hardened shelters.
It confirmed protected living spaces underground. Thai soldiers continued inspections. Documentation was ongoing. Evidence remained under tight control.
Boost for border peace as 18 Cambodian prisoners of war are repatriated after 72 hour ceasefire holds
Peace and war being weighed on both sides of Thai Cambodian border as tensions began to rise again
Ceasefire signed Saturday sees hostilities wind down for 72 hour monitoring period in wider peace deal
Meanwhile, Thai authorities repeated that the situation was calm. However, they underlined that reassurance would depend on stability over time. Monitoring operations would continue without interruption. Forces would remain on alert.
Certainly, while the situation remains calm at the border front, the tunnel system discovered and revealed on Thursday speaks to something vastly different to mere skirmishes or accidental clashes. It shows Cambodia laying the groundwork for a prolonged struggle.
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Further reading:
Peace and war being weighed on both sides of Thai Cambodian border as tensions began to rise again
Outline peace deal agreed at border talks but cabinet approval needed before Defence Minister signs
War to continue says PM Anutin. Dismisses President Trump’s ceasefire talk as a ‘misunderstanding’
Confusion after Trump’s 20 minute phone call with PM Anutin. US side claimed a ceasefire was agreed
