Escalation of military exchanges could move towards war, Acting Thai PM Phumtham Wechayachai says.

The death toll from clashes between Thai and Cambodian troops has risen to 15 in Thailand and one in Cambodia, according to authorities, as more than 120,000 people living along both sides of the border separating the two countries flee the ongoing fighting.

Deadly fighting continued for a second day on Friday as both countries traded heavy artillery and rocket fire, the bloodiest military confrontation between the two Southeast Asian neighbours in more than a decade.

The escalation of military exchanges could move towards war, Acting Thai PM Phumtham Wechayachai told reporters on Friday. For now, the clashes have involved heavy weapons, he added.

The ongoing clashes have taken place in 12 locations along the disputed border, up from six the day before, a Thai military official said on Friday, indicating a widening of the fighting. Rear Admiral Surasant Kongsiri, a military spokesperson, told a press conference Cambodia had continued to use heavy weapons.

“Thai forces have responded with appropriate supporting fire in accordance with the tactical situation,” the Thai military said in an earlier statement.

Thailand’s Ministry of Public Health reported that at least 14 civilians and one soldier were killed in Thailand when fighting broke out on Thursday, and a local provincial official in Cambodia’s Oddar Meanchey border province told the Reuters news agency that one person was killed and five wounded in Thai attacks.

More than 30 Thai civilians and 15 soldiers were also injured, according to Thailand’s Health Ministry, while some 100,672 people from four Thai provinces bordering Cambodia have been moved to shelters, Thailand’s Ministry of Interior was quoted by AFP news agency as saying.

Arsit Sampantharat, the Thai Interior Ministry’s permanent secretary, was quoted by the country’s Channel 3 television channel as saying that more than half of those evacuated were from Surin province, while the rest were from the provinces of Sisaket, Buriram and Ubon Ratchathani.

Citing officials in Cambodia’s Preah Vihear province, the Khmer Times news organisation said that about 20,000 residents have evacuated from the country’s northern border with Thailand.

Shelling from Thailand was also reported before dawn on Friday, the Khmer Times quoted the Cambodian military as saying.

Cambodia’s Ministry of Culture and Fine Arts claimed that Thailand’s strikes had caused “substantial damage” to the Preah Vihear temple, a UNESCO-listed World Heritage Site, according to The Phnom Penh Post.

Diplomatic sources told the AFP news agency that the United Nations Security Council will hold an emergency meeting on Friday to discuss the border fighting.

On Thursday, Thailand said it scrambled an F-16 fighter jet to bomb targets in Cambodia, while Cambodian forces launched long-range rockets towards civilian areas along the Thai border, Thailand’s military said.

Both countries have blamed each other for starting the clashes in a disputed area of the border, which quickly escalated from small arms fire to heavy shelling.

The United States, a longtime treaty ally of Thailand, has called for an immediate end to the hostilities.

China, a close ally of Cambodia, said it was deeply concerned about the ongoing conflict and hoped that both countries “will properly solve their dispute through dialogue and consultation”.