The incident took place this morning at 2am GMT at the three-day event in the municipality, of Landgraaf, south-east of the Dutch country.
It happened as revellers began to pack up their tents and belongings and left the event.
A spokesperson for the police said the hit-and-run may have been caused deliberately but were not sure either way.
Belgian and German police had joined forces to find a white Fiat Doblo van, which according to witnesses had a Dutch licence plate with the numbers 257 on it.
The van was found a short time later, abandoned on the street where the incident happened by one of the campsites.
Though some had also described it as a small white minibus.
The street where the incident happened has now been closed and authorities are still on the scene investigating.
PinkPop festival organisers took to Facebook and said they were “deeply shocked” by the news.
The event had come to end after a performance by US superstar Bruno Mars in front of thousands.
Other acts to have performed at the much-anticipated event include Jessie J, the Foo Fighters and Noel Gallagher.
PinkPop is one of the world's longest running annual music festivals and was launched in 1970.
A helecopter arrived on the scene within moments, witnesses said.