According to police, Nguyen Huu Trung, 39, of Krong Pa District came to the house of Thai Thi Lieu, 31, and Nguyen Dang Ha, 36, early on Friday.
He repeatedly stabbed Ha, who was sleeping on a camp bed outside his house, with a knife.
Upon hearing the noise, Lieu, who was sleeping inside the house, ran out. Trung stabbed her many times as well.
Lieu tried to run, but collapsed very soon.
When neighbors discovered the couple lying in a pool of blood, Trung had already fled the scene.
Ha was confirmed dead while Lieu died shortly after reaching the hospital.
According to the couple’s family, there were no conflicts between them and Trung before the murder.
The couple had two children – four and nine years old.
Police said Trung was hiding in a forest in the area.
Trung’s family said he had been mentally ill for years, and his condition had worsened recently.
Thai Thi Lan, Trung’s wife, said he had been sleeping for just one or two hours of late.
“There were many times when he threatened to set our house on fire with gasoline, but was prevented from doing so,” she said.
His family, however, did not take him to hospital for treatment because they believed there was a “ghost” inside him.
They spent a lot of money on hiring sorcerers from northern provinces to conduct rituals at home and exorcise the ghost.