UPDATED: Fire burning at former Umatilla Chemical Depot

Several buildings have burned at the former Umatilla Chemical Depot as a wildfire has spread across the wildland on the eastern edge of the depot property, according to the Hermiston Fire Department.

The fire burned over multiple concrete bunkers, or igloos, where chemical weapons were once stored. The depot no longer stores chemical weapons and the incineration plant used to destroy them has been torn down.

However, some agencies have used the bunkers to store equipment.

An estimated 3,000 acres had burned as of 3:30 p.m., said Hermiston Fire Capt. J.W. Roberts.

The fire is believed to have been caused by simulated artillery training being conducted Monday morning by a National Guard post on the depot, he said.

The fire spread across Interstate 82 at one place into farmland, but was stopped before it got far, Roberts said.

Interstate 82 was closed for several hours in both directions from Powerline Road at milepost 5 to Westland Road at milepost 10 near the state border because smoke was limiting visibility. The interstate reopened about 2:30 p.m.

Multiple cars or motorcycles crashed before the interstate was shut down. Three people were taken to the Hermiston hospital and one was flown to Kadlec Regional Medical Center in Richland, Roberts said.

Information about which buildings burned was not immediately available.

This story was originally published May 23, 2016 at 12:23 PM with the headline "UPDATED: Fire burning at former Umatilla Chemical Depot."