
The Criminal Court originally sentenced Somkid Phumpuang to death for killing Warunee Pimpabutr in January 2005 but later commuted the sentence to life imprisonment, citing his confession during the police investigation and trial.
Somkid, 45, remains in court custody awaiting four other trials for his alleged murders of four other victims later over a sixmonth period.
His lawyer said yesterday's life sentence would be appealed.
Somkid was also handed a threeyear prison term for stealing the victim's valuables.
Court documents indicate Somkid took Warunee to room 609 of the Ploy Palace Hotel in Mukdahan on January 30, 2005, where they argued over her service fee. He drowned her in the bathtub and absconded with her valuables.
Four more victims were later killed in other northeastern hotels, prompting a public outcry and subsequent massive police hunt for the killer before Somkid was arrested on June 29 of that year. Warunee, 25, was the youngest victim. The other four were in their late 30s.