Armed clashes between Thailand and Cambodia entered a second day on Tuesday, both sides said, in defiance of calls from the United States to stop fighting and adhere to a months-old Trump-backed peace deal that now looks on the brink of complete collapse.

At least eight people have been killed since the latest skirmishes began, according to reports from both sides. By Tuesday, the fighting had spread to more points along the disputed border, with accusations of rocket strikes and drone attacks in some areas.

About 400,000 people living along the border that divides the Southeast Asian countries have been evacuated in the latest flare-up.

And Thai Foreign Minister Sihasak Phuangketkeow hinted the clashes could escalate, telling CNN in a sit-down interview that military action would continue “until we feel that sovereignty and territorial integrity are not challenged.”

The fighting, over decades-old competing territorial claims along their 500-mile (800-kilometer) land border is the heaviest between Thailand and Cambodia since a deadly five-day conflict in July.

The already shaky peace agreement, signed in October in the presence of US President Donald Trump, who hailed it as proof of his ability to end wars, now looks in danger of disintegrating.

Here’s what to know.

Why are they fighting again?

We don’t exactly know.

Both sides accuse each other of firing first, and CNN is unable to verify who did.

Cambodia had been mobilizing heavy weapons and repositioning combat units, the Thai air force said.

Cambodia’s Ministry of National Defense denied the allegations. The Cambodian army said Thai forces had “engaged in numerous provocative actions for many days,” without specifying details.

On Tuesday firing was reported in six of the seven Thai provinces that share a border with Cambodia, according to the Thai military.

The navy said Cambodian troops fired heavy weapons, including BM-21 rockets, into civilian areas, and accused Cambodia of deploying special operations units and snipers to the border, of digging trenches to fortify positions, and encroaching into Thai territory in the coastal Trat province “in a direct and serious threat to Thailand’s sovereignty.”

Cambodia’s army said Tuesday that Thailand’s military had carried out “uninterrupted firing throughout the night” in several border areas using “large-scale drones” and “poisonous smoke.”

Seven Cambodian civilians were killed and about 20 others wounded, according to the country’s Interior Ministry. Thailand said one of its soldiers was killed.

How bad could this get?

The United Nations Secretary General and the European Union have urged restraint from both sides. And a senior US administration official told CNN Monday that “President Trump is committed to the continued cessation of violence and expects the governments of Cambodia and Thailand to fully honor their commitments to end this conflict.”

But there appears to have been little in the way of de-escalation on the ground.

Thai Foreign Minister Sihasak told CNN that Thailand wouldn’t rule out further strikes, saying that military action would continue “until we feel that sovereignty and territorial integrity are not challenged.”

And on Monday, Thailand’s Prime Minister Anutin Charnvirakul told reporters in Bangkok that “Cambodia must comply with (Thailand), in order to stop the fighting.”

When asked about the Trump-backed peace agreement signed in Malaysia, he said: “I don’t remember that anymore.”

Hun Sen, the influential former leader of Cambodia and current Senate President said in a Facebook post Tuesday, “our armed forces of all types must strike back at all points where the enemy attacks.”

The fiery rhetoric underscores the entrenched suspicion and distrust between the two neighbors that has come to define their relationship since the deadly July conflict that killed dozens of people and displaced about 200,000 on both sides of the frontier.

What about that ceasefire?

That agreement was signed in Malaysia in October. Trump, who presided over the ceremony, had helped broker it – in part, by threatening he would not make trade deals with either country if they refused.

But tensions had been simmering for weeks, including a landmine explosion that injured four Thai soldiers in November.

Following that blast, Thailand suspended all work on the peace agreement, and accused Cambodia of violating the joint declaration by laying fresh landmines – a claim Cambodia vehemently denies. The tentative release of 18 Cambodian prisoners of war captured during the July fighting was also halted.

Trump had considered the peace agreement as a major diplomatic victory, and another boost to his much vaunted – and often over-exaggerated – campaign to have ended several wars.

The dispute has its origins in the mapping of Cambodia’s border by its former colonial ruler France, and analysts had cautioned of a long road ahead before a lasting peace deal would be achieved. The peace declaration did not resolve that territorial dispute.

Asked by CNN if Thailand was planning to discuss the latest border clashes with Trump, Sihasak, the Thai foreign minister, said it was up to Cambodia and Thailand to “work things out.” (CNN)

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