Police in the southern province of Dong Nai on Sunday arrested two young men who were carrying a gun and used it to threaten them.
Police on a routine patrol found Duong Van Chinh, 18, and Nguyen Van Tuan, 23, both from the Mekong Delta, were behaving suspiciously, so they were stopped and asked to show their personal papers.
One of the youth, the police have not said which, pulled a gun loaded with seven bullets, and threatened the police. The gun was seized later.
Chinh and Tuan said they had brought the gun to scare some people in the area who were harassing their girlfriends.
They claimed that a person in Ho Chi Minh City gave them the gun as well as two grenades as gifts.
Owning a gun without a valid license is illegal in Vietnam.