The city's police announced Friday Nguyen Thi Kim Sau, a resident of An Hai Ward, has been arrested to be investigated for "murder."
The victim's elder son, 19-year-old Nguyen Thai Bao, has also been detained. The younger son, Nguyen Quoc Huy, was 14 at the time of the incident, placing him below the age of full criminal responsibility under Vietnamese law. Investigators are preparing procedures to send him to a reform school.
According to the investigation, Sau married the victim, 42-year-old Nguyen Chien Thang, last year. Bao and Huy are both his sons from a previous marriage.
Authorities allege that during family disputes, Sau repeatedly told the boys their father intended to leave his assets to a child he purportedly had with another woman.
She is accused of encouraging the two brothers to kill their father, promising she would manage the estate and eventually divide the property between them, even guaranteeing she would take care of Bao after he completed any resulting prison sentence.
