The RCMP say 28-year-old Jason Patrick Foster and a friend were attacked by three other men at the Hedley concert at the Encana Event Centre Feb. 14.
Police say the fight continued into the men's washroom until another man intervened to break it up.
Foster was found unconscious and died later in hospital.
The three suspects were arrested but later released and police say charges are pending.
They say Foster had been living in the Fort St. John, B.C., area but was originally from Manitoba.