One person is dead after a crash in northwest Alberta that included a tractor-trailer carrying explosives, RCMP said Monday.

The crash, which happened just after noon Monday, closed Highway 40 about 50 kilometres south of Grande Cache.

There were three vehicles involved in the accident, not the four earlier reported, police said.

The driver of a Ford pickup traveling south on Highway 40 may have lost control after hitting the shoulder, police said. His truck crossed in front of the tractor-trailer and was hit. Emergency crews used the jaws of life to pull him from the cab, but he did not survive the crash.

Experts in explosives transferred an inert explosive chemical — earlier feared to be dynamite — from the transport truck, so that the chemical could be removed from the site.

The drivers of the tractor-trailer and the other vehicle involved were not injured.

Highway 40 is expected to remain closed until around 8 p.m. Monday.