Officers from Wichit Police Station responded to a report of a fatal assault at a row of shophouses near Soi Thanit at around 10:50pm. The incident occurred in room number 04, next to Soi Thanit Thurakij.
At the scene, police found the body of Supattra Sangthong, 28, lying with signs of severe assault, including facial bleeding and extensive bruising across her body.
Her boyfriend, Hatthanai Yuttitham, was found inside the room and taken into custody.
During questioning, Hatthanai admitted to physically assaulting Ms Supattra by slapping and punching her in the head, causing her to lose consciousness. She later died from her injuries.
Investigators believe Hatthanai was under the influence of cannabis at the time of the incident.
Forensic officers and a doctor from Vachira Phuket Hospital examined the scene and arranged for the body to be taken for a full post-mortem examination to confirm the cause of death.
Hatthanai was formally arrested at the scene and is now facing legal action, Wichit Police confirmed.