COLUMBIA FALLS, MT (From news reports) -- Columbia Falls residents near the Weyerhaeuser facility reported hearing an explosion coming from the facility.

According to sources with connections to the Weyerhaeuser medium density fiberboard (MDF) plant, the employees who were on shift at the time were all reportedly accounted for.

One employee said employees work 12 hour shifts beginning at 7:30 a.m. and 7:30 p.m., saying the explosion allegedly happened soon after the night shift crew came on.

Some Columbia Falls residents reported seeing smoke soon after the explosion.

Weyerhaeuser officials were not immediately able to provide any details.