Cross-border fighting between Thailand and Cambodia entered its third consecutive day on Wednesday, with artillery exchanges and air raids forcing more than half a million civilians to flee their homes in one of the most serious escalations between the two Southeast Asian neighbors in recent years.

According to Thailand’s Ministry of Defence, more than 400,000 civilians have been moved into emergency shelters across seven Thai provinces amid what authorities described as an imminent threat to civilian safety. Spokesperson Surasant Kongsiri said mass evacuations were necessary due to ongoing shelling and aerial attacks near populated areas.

The Thai military reported that rockets fired from Cambodian territory landed near Phanom Dong Rak Hospital in Surin province, forcing patients and medical staff to take cover in underground bunkers on Wednesday morning.

In Cambodia, the Ministry of National Defence said 101,229 people had been evacuated to safe shelters and relatives’ homes across five border provinces. Spokeswoman Maly Socheata accused Thai forces of intensifying air and artillery strikes.

Reports from Cambodian media outlet Cambodianess said Thai F-16 fighter jets targeted at least two areas inside Cambodian territory, while sustained artillery fire struck three other locations. Thailand’s Matichon Online confirmed that Thai F-16s were deployed to hit what Bangkok described as a Cambodian military target along the disputed border.

Thailand’s The Nation newspaper, citing military sources, reported that Cambodian rockets and artillery bombarded at least 12 frontline areas in four Thai provinces early Wednesday, though no immediate casualty figures were confirmed. Thai military officials said clashes were reported in almost all Thai provinces bordering Cambodia, with Surin province alone witnessing fighting in at least five separate locations.

The current round of violence is the deadliest since clashes in July, which killed dozens and displaced around 300,000 people on both sides of the border before a fragile truce was brokered.

Responding to the renewed fighting, U.S. President Donald Trump said he intended to intervene diplomatically, announcing that he would make a phone call in an effort to halt the conflict. However, Thai Foreign Minister Sihasak Phuangketkeow told Al Jazeera that he saw no immediate prospects for negotiations and insisted Thailand did not initiate the clashes.

Cambodia’s Defence Ministry said its forces were compelled to act in response to what it described as indiscriminate Thai shelling of civilian areas, an accusation Bangkok strongly denied.

In a further sign of deteriorating relations, Cambodia announced it was withdrawing from the Southeast Asian Games currently being hosted in Thailand, citing serious security concerns.

Tensions have steadily risen since Thailand suspended de-escalation measures that had been agreed at a summit in Kuala Lumpur last October. The agreement, which was reached in the presence of President Trump, began to unravel after a Thai soldier was seriously injured by a landmine that Bangkok claimed was newly planted by Cambodian forces — an allegation Phnom Penh has rejected.

The roots of the conflict stretch back more than a century to colonial-era border demarcations and competing claims over historic temple sites along their largely undemarcated 800-kilometer frontier, a dispute that has periodically erupted into armed confrontations. (ILKHA)