A van ran into a group of attendees at the Dutch festival Pinkpop on early Monday morning, killing one and injuring at least three people.
The 34-year-old man in is now in custody and is being held on suspicion of manslaughter and attempted manslaughter.
'The white van that was involved in the collision is still being sought, ' police said in a statement, adding they had set up an emergency call centre for information.
The authorities would not give more details because the investigation was still ongoing.More news: John Travolta’s ‘Gotti’ Fires Back at Critics After 0% Rotten Tomatoes Score
The crash happened at the end of the three-day festival, which featured singer Bruno Mars as its closing act and attracted about 45,000 people.
"This investigation is still underway and we can not say whether this was something intentional or an accident", said police spokesman Hub Haenen. Pearl Jam, Foo Fighters and Bruno Mars headlined Pinkpop 2018, which sold out all its 45,000 weekend tickets in April.
The condition of the three injured people is not yet known.
Police cordoned off the section of the road while an investigation is under way, and a police helicopter was deployed to take aerial shots of the crash site.
The organization of the PinkPop festival said it was "deeply shocked" and also expressed their "compassion with the victims and family".