YouTube footage showing dozens of cars parked along a Khanty-Mansiisk region road after being stopped by police.
Surgut police said a possible mass brawl was squashed after they detained more than 160 people traveling in an armed motorcade toward the Siberian city.
The police said they pulled over about 90 cars making the hourlong drive from Nefteyugansk to Surgut on Sunday.
Inside the vehicles they found an unspecified number of traumatic pistols, knives and other weapons.
"Thanks to the efficiency of the police, we managed to prevent any disturbance of public order," the police said in a statement.
It said an investigation had been opened and, based on its outcome, a decision would be made on whether to press charges against the detainees.
Footage of Sunday's incident showed dozens of cars parked along a road as police searched each vehicle. The video was taken by a passing car and uploaded to YouTube.
The police investigation was certain to explore any connection between the car convoy and a nearly adverted mass brawl at a Surgut market on April 13. The crowd of ethnic Russians and North Caucasus natives gathered at the market after a group of ethnic Russians beat up a Chechen native for criticizing them, news reports said. Police detained 180 people with clubs, iron rods, hammers, air guns and other weapons.
But local police have said that they do not see any racial component to the incident.
The car convoy also might have been harmless. Surgut Inform television reported that the detainees might have been members of a car fan club that had planned to drive to Surgut from several cities in the Khanty-Mansiisk region to stage an Easter rally and charity drive at a local orphanage. Russian Orthodox believers celebrated Easter on Sunday.
The YouTube user who published the convoy video also said the police had stopped members of the car club.