The family's minivan collided with an oncoming truck on Highway 16 east of Tete-Jaune, B.C. DriveBC
A major avalanche closed Highway 16 near Valemount, B.C., on Monday morning and police say it is not yet known if any vehicles were caught in the slide.
Officials said the avalanche buried a 400-metre section of the mountain highway on Shale Hill near Mount Robson around 9:30 a.m. PT.
An avalanche technician was flown into the area to conduct a survey of the area by helicopter.
"Highway 16 East is completely blocked and there are no detours available. Ministry of Transportation continue to assess the incident," said the statement issued by Const. Lesley Smith.
"Lakes District maintenance crews are on scene assessing the scale and scope of the slide. It is currently unknown if any vehicles were involved or caught in the avalanche," said the statement.
"Ministry of Transportation has advised that the risk of additional slides is very high and it is too dangerous to enter the current slide area to look for vehicles."
A 79-kilometre section of the route has closed in both directions from the junction with Highway 5 in Tête Jaune Cache to the Alberta border while officials assess the situation.
Hwy. 1 also closed near Revelstoke
The slide comes after several days of heavy snowfall across southern B.C. that put the avalanche danger rating in the area at "considerable" and "high" depending on the elevation.
Sections of the Trans-Canada Highway were also closed Monday in both directions from Revelstoke to Lake Louise because of high avalanche danger.
Avalanche control is also underway on highways 31 and 37A on Monday.
Since Christmas, at least eight people have been killed in accidents on Highway 16, which runs through some of the most rugged mountainous areas of B.C. Police have blamed the deaths on dangerous winter driving conditions.
Google Maps: Tête Jaune Cache