Hanoi police are hunting for a man who they said had stabbed a traffic officer after being pulled over on Monday.
The incident happened at 7:45 a.m. when a group of five police officers were regulating traffic at the corner of Tran Phu and Chien Thang in Ha Dong District, the media reported.
They ordered Nguyen Tien Duc and Nguyen Duy Hien to stop. The men were riding a motorbike without helmets and rear-view mirrors.
Duc attempted to flee but the officers stopped him.
He began to insult the officers and suddenly took out a knife and stabbed senior lieutenant Ngo Duc Binh.
He ran away and threatened a passer-by into helping him escape.
Police seized the bike and took Hien to a station for investigation.
This is the second attack against police officers within a week.
Vinh Long police announced that have arrested two men for assaulting a traffic police officer in the southern province on January 23.
Huynh Phuc Vinh, 34, and Vo Quang Phuong, 40, were speeding on a motorbike and ignored the police's order to stop at a checkpoint on the National Highway 54, investigators said.
After being chased by officer Nguyen Minh Phuong, they stopped the bike and attacked him with their helmets.