A man was stabbed and another man was injured in the stomach during the EDC event at the National Bowl on Saturday.
Police are linking the two incidents of grevious bodily harm and are appealing for witnesses.
The first offence happened at around 3.30pm when a man was lying on the embankment by gate six. The 21-year-old was approached from behind by a man. He was then stabbed by the offender.
The second GBH occurred at around 6pm near the bar to the left of the arena as you look at the stage.
The victim, a 27-year-old man, was in a fight with another man during which he received a puncture wound to his stomach.
Both victims received treatment at Milton Keynes General Hospital and have since been discharged.
The offender is white, with light-colour hair. He was wearing a blue T-shirt and shorts.
A 25-year-old man from Liverpool has been arrested on suspicion of GBH. He has been released on police bail until August 30.
Investigating officer, Det Con Gregory Hughes of Force CID based at Milton Keynes police station, said: “These offences are believed to be linked due to their close proximity to each other and the similar descriptions of the offender.
“We are urging anyone who attended yesterday’s event and took photographs near either location of the offences to contact police by calling 101.
“Further, anyone who witnessed the offences, or anyone with any information should also contact police immediately.”
Call the police on 101 or Crimestoppers anonymously on 0800 555 111 or online at www.crimestoppers-uk.org.