The motorbike was running along Dinh Le Street in District 4 at around 1 p.m. when it collided with another vehicle running in the same direction at an intersection with Le Quoc Hung Street before ramming into a nearby food stall.
All four people on the two vehicles were injured and taken to the hospital. Swords and a pitchfork were seen lying on the ground at the accident site.
One witness said that when the incident happened, the motorbike carrying the three armed people was running at very high speed and was followed by another motorcycle.
"It could be that the group was committing some crime when they were busted by the police who chased after them," said the witness who requested anonymity.
The police are investigating the accident.