I don't know what VIPR squad is doing, but it seem pretty much as European customs officers under Schengen region.

Since there are no border customs checks any more in Schengen area, the customs officers have authority to stop any vehicle and to strip it bare, while searching for a cause for an investigation.

In Slovenia as of this year, customs officers are allowed on private land to perform an inspection of fuel for vehicles (heating oil is basically diesel with lower tax and often used in heavy and farm machinery).