Thousands fled the Thai-Cambodia border on Monday after deadly clashes killed at least five people. Residents on both sides evacuated amid fresh violence, the worst since a July ceasefire. Both countries blamed each other. Thailand’s Prime Minister Anutin Charnvirakul said his country “never wanted violence” but will “use necessary means to preserve its sovereignty.” Meanwhile, Cambodia's former leader Hun Sen called Thai “invaders” provocative. Fighting erupted in Thailand’s Ubon Ratchathani Province and Cambodia’s Preah Vihear province. One Thai soldier and four Cambodian civilians died, with about a dozen wounded. Thai teacher Siksaka Pongsuwan warned that children near the border are losing precious learning time. Nearly 650 schools in five Thai provinces closed due to safety concerns. In Cambodia, social media shared chaotic clips of parents rushing to take kids home. Past clashes in July also disrupted schooling, with some students unable to attend online classes due to lack of internet. The border dispute dates back over 100 years. It flared sharply after a Cambodian rocket attack in July, followed by Thai air strikes. A ceasefire was brokered but recent violence has undermined peace efforts. Thailand suspended the ceasefire after landmine injuries. Cambodia nominated US President Donald Trump for a Nobel prize for helping broker the deal. Tensions remain high as the two neighbors fight over an 800km border drawn after French colonial rule.