Police in Tien Giang Province have arrested 63 people they said are gangsters with machetes and other deadly weapons who were on their way to fight a rival group.
Officers on patrol Tuesday night spotted two vans that looked suspicious because they carried young men, most of them with large tattoos.
They fired warning shots to stop the vehicles, in which they found dozens of machetes and knives, iron bars and electric whips.
Preliminary investigation suggested that a small criminal group in Tien Giang was in conflict with a bigger group over shark loan lending and cock fighting organization in the area.
The small group then asked for help from Tien Giang's notorious criminal kingpin, named Bao, who in turn gathered the men from various groups across the Mekong Delta.
Bao drove a different car and has escaped, police said.
Police are investigating further.