Chinese military cargo planes delivered rockets, artillery shells, and mortars to Cambodia weeks before a simmering border dispute with Thailand erupted into a brief but deadly war in July, according to Thai intelligence documents reviewed by The New York Times.
The reports, authenticated by senior Thai military officers, state that six Y-20 transport aircraft — nicknamed “Chubby Girls” in China for their size — landed in Sihanoukville between June 21 and 23. The planes carried 42 containers of munitions that were later moved to the contested border region near the ancient Preah Vihear temple, claimed by both countries.
The shipments, which have not previously been reported, coincided with Cambodia’s military buildup along the frontier, including new roads and a military base visible in satellite images. Analysts told the Times the moves signaled a far more aggressive posture than in past standoffs.
Fighting erupted in late July, lasting five days and leaving at least 40 people dead and hundreds of thousands displaced. Thai authorities said Cambodian rockets struck a gas station, a hospital, and homes, killing at least 13 civilians. Thailand responded with F-16 airstrikes that quickly reasserted its military superiority.
Cambodian defense officials did not deny the shipments but said the weapons movements aligned with the conclusion of joint exercises with China’s People’s Liberation Army in May. China’s Defense Ministry has denied arming Cambodia for use against Thailand.
Independent monitors have corroborated elements of the Thai intelligence, particularly that much of the weaponry used by Cambodia was of Chinese origin. Fortify Rights, a human rights group, said Cambodian forces fired Chinese-made rockets at Thai provinces during the conflict.
The revelations complicate Beijing’s effort to cast itself as a neutral broker in Southeast Asia. China worked behind the scenes to mediate the ceasefire even as its weapons appeared to fuel the escalation.
Both Cambodia and Thailand have dramatically increased defense spending in recent years, relying heavily on Chinese arms. Analysts suggest Cambodian leader Hun Sen may have been emboldened by Beijing’s backing, believing his country was in a stronger position than during past clashes.
The border dispute centers on ancient temples along a frontier demarcated during French colonial rule. While an international court ruled in the 1960s that Preah Vihear belonged to Cambodia, Thailand has never fully accepted the decision.
“The entirety of the evidence suggests that there has been a concerted decision by the Cambodian leadership in the months and years leading up to the border clashes to change the status quo,” Nathan Ruser of the Australian Strategic Policy Institute told The New York Times.
The fighting has eased under a fragile ceasefire, but the revelations raise questions about China’s dual role as both arms supplier and peacemaker in one of Southeast Asia’s most combustible border disputes.
