Police were called to the scene, in front of a motorbike shop and a visa service office on Wichit Songkram Rd, at about 8:20am.
Officers arrived to find the man, Petai Hantaku, 32, from Phetchabun, still attacking the woman, his estranged wife Wimon Ketyu, 30.
Officers quickly arrested Petai and had Ms Wimon rushed to Vachira Phuket Hospital. However, Ms Wimon was later pronounced dead from her injuries.
Lt Col Kiattisak Sangmanee of the Kathu Police said the couple previously lived together in Phetchabun.
Petai said he wanted to make things better with Wimon, but she didn’t want to, he explained.
Petai had followed her to his motorbike, sparking yet another argument, this time ending with Petai repeatedly attacking Ms Wimon with a knife.
“It’s a very sad situation,” Lt Col Kiattisak.
Police have yet to confirm the formal charges against Petai, which are presumed to include first-degree murder, among others.
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