Morinville RCMP arrested four people and seized a gun early Sunday morning at the campground on the Boonstock music festival grounds.

Police say officers saw a suspected drug deal.

When they searched the suspects’ vehicle, they found a loaded semi-automatic handgun and quantities of what they suspect to be cocaine, methamphetamine, marijuana and MDMA.

The arresting officers had been assigned to patrol the festival grounds, located about 40 kilometres northeast of Edmonton.