UBON RATCHATHANI, Thailand — The border conflict between Thailand and Cambodia entered its third day on Saturday with renewed airstrikes and rising casualties, despite mounting international pressure for a ceasefire.

Thai fighter jets struck military targets in the Phu Ma Kua area and near the Ta Muen Thom temple, according to Thai news outlet The Nation. Cambodia confirmed the airstrikes and said it responded with retaliatory attacks, according to the Khmer Times.

In response to the escalating violence, Cambodia closed its airspace over conflict zones, while the Thai Navy deployed four vessels in support of its ground forces.

Thai forces also claimed to have taken control of a strategic hilltop roughly 2.8 kilometers (1.7 miles) from the contested Preah Vihear Temple, a UNESCO World Heritage Site that sits at the heart of the border dispute.

The fighting has continued in defiance of calls for de-escalation. Malaysian Prime Minister Anwar Ibrahim reiterated on Saturday his efforts to mediate a ceasefire.

Anwar had said Friday that both sides agreed in principle to halt hostilities during separate calls with his Thai and Cambodian counterparts on Thursday night.

Despite that agreement, clashes have intensified. The UN Security Council held an emergency closed-door meeting in New York on Friday, attended by representatives from both countries.

“We asked for an immediate ceasefire—unconditionally—and we also call for a peaceful solution to the dispute,” Cambodia’s UN Ambassador Chhea Keo said.

Thailand submitted a letter to the Security Council accusing Cambodia of provoking the conflict and urging the international community to support “the immediate cessation of hostilities and the resumption of dialogue in good faith,” according to Thai PBS.

Cambodia, meanwhile, called on the UN’s tourism agency to condemn Thai airstrikes that reportedly caused severe damage to the ancient Preah Vihear Temple.

China denied allegations that it had supplied military equipment to Cambodia.

Authorities on both sides have evacuated thousands of civilians from border regions. Thai officials reported 20 fatalities, including six soldiers, while Cambodia said 13 people, including five soldiers, were killed since hostilities reignited on Thursday.

The flare-up follows renewed tensions that began May 28, when a Cambodian soldier was killed near the disputed boundary between Cambodia’s Preah Vihear province and Thailand’s northeastern Ubon Ratchathani province. — Agencies