Dang Van Hung was arrested for allegedly killed four members of a family in the northern province of Yen Bai on August 12.
Vietnamese police on Saturday arrested a man who allegedly killed four people in a family, including a 2-year-old boy, in a northern mountainous town four days ago.
Dang Van Hung, 26, was apprehended when he and his girlfriend Nguyen Thi Huong, 36, were hiding in a forest in Yen Bai Province, a few kilometers away from the crime scene, police said.
Hung was identified as a suspect based on a victim's phone call to her father when the murders happened.
Huong, whose involvement in the crime is unclear, was also taken into custody.
According to Col. Pham Ngoc Thang, deputy chief of Yen Bai police, Hung confessed to killing 32-year-old Tran Van Long as well as Long's wife Hoa, two-year-old son, and sister-in-law Ha on Wednesday afternoon.
Hung said he killed Long and the others after their argument over conflicted farm land and water stream turned violent, Col. Thang said, adding that the police is investigating into other possible motives.
The victims' bodies were found by relatives of Long's wife lying in and around Long's makeshift house in a field in Van Yen District, sustaining fatal knife injuries.
Dang Van Hung (L) and Nguyen Thi Huong.
Long's father-in-law told the police that he rushed to the scene after receiving a phone call from his daughter, who said Long was being beaten by Hung before suddenly hanging up.
Hung's father said his son returned home and told him that he had killed Long. He said Hung carried two home-made rifles when he fled.
The police said Hung was not armed when he was arrested.
Hung claimed he had thrown away the knife he used in the murder.
Col. Thang said the police believed Hung is the sole suspect in the murders.
Investigation is underway.