Cambodia Security Report — March 21, 2026

Security analysis based on open-source intelligence and web research. Period: March 14 — March 21, 2026.

Executive Summary

Cambodia’s security environment during March 14-21, 2026 is dominated by the ongoing border conflict with Thailand, which escalated into sustained armed conflict in 2025 resulting in over 100 deaths and the displacement of more than 500,000 civilians. While a ceasefire declared in late December 2025 remains nominally in effect, Prime Minister Hun Manet has accused Thai forces of continuing to occupy Cambodian territory “deep” beyond even Thailand’s own claims. Domestically, the government is intensifying its crackdown on online scam compound operations, with new fines taking effect in March 2026. Political repression continues, with the Supreme Court rejecting appeals from imprisoned environmental activists on March 2. The government faces a complex strategic landscape balancing the border crisis, the scam economy cleanup, and managing great power relationships.

Thailand-Cambodia Border Crisis

Conflict Background

The most serious Cambodia-Thailand military confrontation since 2011 erupted in May 2025 with a skirmish near the Preah Vihear temple complex that left a Cambodian soldier dead. Fighting escalated through the second half of 2025, resulting in more than 100 deaths and the displacement of over 500,000 civilians — a devastating humanitarian toll for both nations.

The dispute stems from unresolved boundary demarcation issues dating to the Franco-Siamese treaties of 1904 and 1907. While the International Court of Justice ruled in 1962 that the Temple of Preah Vihear belonged to Cambodia, the status of surrounding land was left ambiguous, creating the basis for recurring territorial disputes.

Current Ceasefire Status

A 72-hour ceasefire announced on December 27, 2025 has been extended and remains nominally in effect. However, Cambodia has repeatedly accused Thailand of violations. The Royal Government spokesperson stated on February 16, 2026 that Thai forces continued to damage civilian infrastructure and government buildings inside Cambodian territory.

Prime Minister Hun Manet, while traveling to Washington for a meeting of President Trump’s Board of Peace, stated that Thai forces continue to occupy “deep into Cambodian territory in many areas, further beyond even Thailand’s own unilateral claim.”

Thai Border Fence Construction

Thailand announced plans to begin construction of a border fence along its frontier with Cambodia in April 2026. The pilot phase will cover approximately 1.3 kilometers in Chanthaburi Province. While Thailand frames this as a security measure to curb cross-border crime, Cambodia views it as a provocative act that could consolidate Thai control over disputed territory.

Military Readiness

The Royal Cambodian Armed Forces (RCAF) remain on heightened alert along the Thai border. While significantly outmatched by Thailand’s military in conventional capability, Cambodia’s forces have demonstrated resilience during the 2025 fighting. The conflict has accelerated discussions about military modernization, though Cambodia’s limited defense budget constrains major procurement.

Internal Security & Political Governance

Scam Compound Crackdown

Prime Minister Hun Manet has vowed to eradicate the “black economy” as Cambodia intensifies its campaign against online scam networks. Starting from March 2026, authorities are imposing fines under a sub-decree signed by Hun Manet in January:

• Failure to obey regulations: 400,000 riel fine
• Accommodation owners concealing foreigners illegally: 4,000,000 riel per foreign national

Phnom Penh Governor Khuong Sreng pledged to completely eliminate online scam operations from all areas of the capital by mid-March 2026. However, analysts note a significant gap between government promises and reality — scam compounds continue to operate, particularly in border areas such as Sihanoukville and along the Thai and Vietnamese borders, with many operations linked to Chinese criminal networks.

Political Repression

The Supreme Court rejected appeals from five imprisoned Mother Nature environmental activists on March 2, 2026. These activists had been sentenced for advocacy exposing connections between state corruption and ecological damage. Five additional activists from the group remain abroad or in hiding.

Human Rights Watch’s World Report 2026 characterizes Cambodia as maintaining systematic political repression under Hun Manet’s government, noting that the “illusion of reform” under the leadership transition from Hun Sen to his son has given way to continued authoritarian governance.

US-Cambodia Relations

Deputy Secretary of State Landau met with Prime Minister Hun Manet in February 2026, signaling continued US engagement with Cambodia despite human rights concerns. The meeting reflects Washington’s strategic interest in maintaining influence in a country with deep ties to China, particularly given Cambodia’s hosting of the Ream Naval Base, which China has been upgrading.

China-Cambodia Relations

Strategic Partnership

Cambodia remains one of China’s closest partners in Southeast Asia. Chinese investment continues to flow into infrastructure, real estate, and special economic zones. The Ream Naval Base in Sihanoukville, where China has constructed military facilities including a dry dock capable of servicing warships, represents the most strategically significant Chinese military presence in mainland Southeast Asia.

Economic Dependence

Chinese-owned businesses dominate key sectors of Cambodia’s economy, particularly in Sihanoukville, where Chinese investment has transformed the coastal city. While some Chinese operations have been linked to the scam compound industry, the economic relationship extends across construction, manufacturing, and agriculture.

Regional Diplomacy

ASEAN Dynamics

Cambodia’s border conflict with Thailand tests ASEAN’s capacity for internal conflict management. The organization’s principle of non-interference limits its ability to mediate, though regional pressure for de-escalation continues behind closed doors.

Mekong Cooperation

Cambodia participates in Mekong subregion cooperation frameworks, including joint drug trafficking interdiction efforts and water resource management discussions. However, tensions over upstream dam construction — particularly Chinese dams on the upper Mekong — continue to affect Cambodia’s water security and fisheries.

Outlook & Assessment

Threat Level: Elevated

Cambodia’s security threat level is assessed as Elevated, driven by:

1. The ongoing border conflict with Thailand, which despite a ceasefire has resulted in continued territorial violations and military tensions
2. The entrenched scam compound industry posing reputational and transnational crime challenges
3. Growing Chinese military presence at Ream Naval Base affecting regional security dynamics
4. Continued political repression constraining civil society and governance accountability

The border conflict with Thailand represents the most acute security concern. While neither side appears to seek renewed large-scale fighting, the unresolved territorial disputes, domestic political pressures in both countries, and the planned Thai border fence construction create conditions for potential escalation. Cambodia’s strategic dependence on China limits its diplomatic flexibility and shapes its security posture in ways that concern regional partners.