One of the men involved in the brawl was thrown out of the party tent at around 2.30am because of his bad behaviour.
The police are now looking for witnesses who might have seen something inside or outside of the tent at that time.
Potential witnesses are asked to contact the Diekirch-Vianden Police Department, either by calling (+352) 244 80 1000 or by writing an e-mail to police.diekirchvianden@police.etat.lu
