WASHINGTON (Reuters) – A fire on Tuesday gutted a storage shed at a U.S. Department of Agriculture (USDA) complex in Maryland that was closed last week because of threats, a fire official said.

The blaze at Building 426 at the USDA’s Beltsville facility took firefighters about two hours to extinguish, Prince George’s County fire department spokesman Mark Brady said by phone, adding there were no injuries.

The fire department and the federal Bureau of Alcohol, Tobacco, Firearms and Explosives are investigating the cause, he said.

“Hopefully, we’ll have some type of resolution, or at least which direction we’re headed, in the near future,” Brady said.

The shed housed workshops for such items as masonry and fire extinguishers as well as storing fuel and maintenance vehicles. WUSA, a CBS television affiliate, quoted workers as saying posters also were stored there.

Smoke continues to emerge from the wreckage of a U.S. Department of Agriculture facility, closed last week due to threats, which burned down at the USDA complex outside of Washington in Beltsville, Maryland, U.S., September 6, 2016. REUTERS/Jim Bourg

Live TV footage showed the wood frame building engulfed in flames, with part of the walls missing and a section of the roof gone as firefighters poured water onto the structure.

A USDA spokeswoman had no details on whether the building was burned to the ground, or if anything was stolen.

Last week, USDA facilities in five states, including the one in Beltsville, a Washington suburb, were closed after receiving anonymous threats.

Scientists at the Beltsville site research poultry diseases, soybean genetics and genetic modification of food animals, according to its website.

(Reporting by Dan Burns, Ian Simpson in Washington and Tom Polansek and Michael Hirtzer in Chicago, editing by Dan Grebler and Alan Crosby)