At least 1 person missing after corn silo collapses in Washington state

At least one person is missing after a large corn silo has collapsed onto a building in Washington, possibly trapping people inside.

Authorities tell Q13 Fox firefighters responded to the structure collapse in Pierce County, which is south of Seattle.

South Pierce Fire & Rescue Chief Bob Vellias said Monday night that a Federal Emergency Management Agency engineer was assessing the building to see whether a search dog could be allowed inside.

Vellias said a male employee in his 50s was believed trapped by tons of grain Monday afternoon. The man was not immediately identified.

The News Tribune reports that the chief says because of lighting issues, rescuers don't expect to be able to fully search the wreckage until Tuesday.

It wasn't immediately clear what caused the collapse, which eventually filled an office and electrical area with corn. The missing worker was in that building.

Vellias said Wilcox Farms officials were not speaking with reporters Monday. A call to the mill rang unanswered. The family farm supplies eggs throughout the Pacific Northwest.

The Associated Press contributed to this report.