According to officials, the shooter used two semi-automatic rifles and two semi-automatic handguns, but only one of the rifles has been traced back to Canada.
"The remaining guns that were recovered are believed to have been obtained from the United States," the RCMP have confirmed.
The calibre of the weapons has not been released.
Regarding the decals on the shooter's car, police say the gunman placed these on his car to disguise his vehicle as an RCMP cruiser.
Police say they have identified the supplier, who stated that the decals "were created without permission of the business owner. The business owner and individual who made the decals are both cooperating with police."
The RCMP is working with over 500 eye witnesses to obtain more information regarding the shooting spree. Officials have confirmed through eye witnesses that the shooter used what is likely gasoline to help ignite a series of fires.
"From witness statements, we know the gunman had a significant supply of gasoline at his home in Portapique," the RCMP say.