Police in the central province of Ha Tinh on Tuesday detained a taxi driver for allegedly killing a passenger to rob her bag.
Initial investigation found 26-year-old Nguyen Van Tien of Mai Linh Group drove Pham Thi Oanh, 23, from Ha Tinh downtown to Thach Ha Commune on July 3 night.
Oanh then requested Tien to bring her back to a hotel in Ha Tinh Town.
On the way to the hotel, he allegedly stopped at a deserted place and strangled Oanh to death before stealing her bag, which contained a mobile phone and VND250,000 (US$11).
A photo of Pham Thi Oanh posted on her facebook page earlier this month.
Tien then dumped her body into a river.
The woman's body was found by local people on Tuesday morning, several hours before Tien was arrested and then confessed to the crime.
The victim was a fourth-year student of the Hue University of Education, which assigned her to be an invigilator for the national high school graduation exam in Ha Tinh Province, as part of her training.
The examination took place nationwide July 1-4 with nearly 900,000 students taking part.