A Vietnamese teacher, his wife and a school friend were killed when a vehicle collided with a motorcycle in the northern city of Ho Chi Minh City on Saturday, police said.
Two people were also injured in the crash, police spokesman Colonel Nguyen Thi Pham said.
The driver of the motorcycle, a 29-year-old woman, was arrested on suspicion of homicide and homicide by auto, he said.
She is the second Vietnamese woman to die in a fatal motorcycle crash this year.
The woman’s family was not immediately available for comment.
The accident happened in the central city of Saigon at around 4:30 p.m. local time, police and local media reported.
No injuries were immediately reported.