Long-festering tensions over border territory have escalated into armed conflict between Cambodia and Thailand, leading to dozens of deaths on both sides and displacing tens of thousands of people.

Thailand and Cambodia exchanged fire along their disputed border for a second day on Friday, officials from both countries said, with more than a dozen people reported killed and more than 135,000 civilians evacuated.

Thailand and Cambodia are engaged in their worst fighting in over a decade, exchanging heavy artillery fire across their disputed border, with at least 16 people killed and tens of thousands displaced.

BANGKOK -- Armed clashes have broken out between Thailand and Cambodia in long-disputed border areas, rapidly escalating months-long tensions.

Cambodia will begin conscripting civilians into its military beginning next year, Prime Minister Hun Manet said on Monday, amid simmering tensions along

Thailand has one of the best-equipped and trained air forces in Southeast Asia, with an estimated 46,000 personnel, 112 combat-capable aircraft, including 28 F-16s and 11 Swedish Gripen fighter jets, and dozens of helicopters.

Thailand favours bilateral negotiation rather than third-party mediation to resolve its military conflict with Cambodia, two Thai officials said, as fighting along their disputed border continued unabated.

"The U.S. already flunked the test and that should be a wakeup call," a former senior U.S. State Department official told Newsweek.