Investigators are looking into what sparked a fire on a semi-trailer that was hauling anhydrous ammonia.
No one was injured in the fire, and the ammonia never leaked, but the highway was closed for over an hour after the fire, which was reported at about 6 p.m. on Tuesday.
The trucker hauling the load of fertilizer was about 15 kilometres west of Shoal Lake, on Highway 16, when the fire was noticed, and was able to safely pull over to the side of the road and detach from the trailer.
Firefighters from Birtle and Shoal Lake were called out and managed to safely douse the fire, but it took some time to cool the trailer before the highway could be re-opened.
Anhydrous ammonia is one of the more dangerous chemicals used in farming, although it is not very flammable.
Yellowhead RCMP are investigating the cause of the fire.