The incident occurred in front of GB Lodge and Bar on Chaweng Beach Road in tambon Bor Pud at about 6am after Volker Schwartges, 46, and his Thai girlfriend Jariya Konkote, 39, left the bar and walked to their motorcycle to return home.
Witnesses told police the couple, who are the owners of “99 Bar” on Chaweng beach, found two teenage boys were sitting on the motorbike drinking beer with a third standing nearby.
Schwartges was unhappy and rebuked them. A fierce argument ensued and escalated into a deadly fight, as the German was assaulted by the teens and at one point fell to the ground.
The witnesses said one of the teens broke a beer bottle and stabbed Schwartges in the neck, killing him.
Ms Jariya tried to stop the fight but failed. Police said the broken bottle cut Schwartges’s carotid artery.
The teens fled and were later apprehended at an unnamed food shop opposite Palm Beach hotel in Bor Pud in the afternoon.
Pol Lt Col Pana Saenathip, deputy chief of Bor Pud police station, said the teenager who stabbed Schwartges was 17 years old and was carrying a 15-cm long knife when police caught him.
His accomplices were aged 14 to 15. The three were charged with collusion to commit murder, the officer said.