A jealous man shot his ex-wife, her mother and a teen relative before turning the gun on himself at a house in Khon Kaen on Saturday, leaving his two-year-old daughter alone and in shock.
The shootings happened at a house in Khampom village of tambon Phon Phek.
Police and rescue workers who rushed to the scene found a woman, identified later as Jaruayporn Faengrit, 50, lying dead on a bed with two gunshot wounds to her body.
Next to the body lay that of her daughter Khalita Faengrit, 28, with two gunshot wounds to her head. Noppadol Unthasee, 55, a former husband of Khalita, was lying dead on a bed with a gunshot to his mouth. The body of Phonphiphat Thongyot, 18, was found dead inside a bathroom with two gunshot wounds to his head.
A two-year-old girl, the daughter of Noppadol and Khalita, was found trembling with shock near the body of her mother.
The house belonged to Mrs Yaowaluck, the mother of dead teenager Phonphiphat. Khalita was a younger sister of Yaowaluck. She had one daughter with Noppadol, who lived in Nong Khai where he owned a resort along the Mekong River.
Khalita had two children from a previous marriage before she married Noppadol.
Police believe the shooting was motivated by jealousy after Noppadol learned that his former wife had become romantically involved with someone else.