Utah-based Dugway Proving Ground, an army base focused on rendering chemical and biological defensive testing and training was placed on lockdown on Wednesday.

The Salt Lake Tribune reported that the lockdown started at 5:24pm. Employees were not allowed to leave or enter the premises. About 1,200 to 1,400 people were present at Dugway when the lockdown occurred.

The Washington Post reported that Base commander Col. William E. King said: We are working as quickly and as thoroughly as possible to resolve a serious concern within the Test Area. There were no reports of damage or injury at the site.

Dugway Proving Ground is located 85 miles southwest of Salt Lake City. The facility covers about 798,214 acres and is used for testing ways of protecting army personnel from a chemical and biological war threat. The base also conducts tests related to the reliability and survivability of military equipment in a chemical or biological war.

On its website the base states its mission as: Dugway's primary mission is testing United States and Allied chemical and biological (CB) defense systems and also performing nuclear, biological and chemical (NBC) contamination survivability testing of defense material.

The base was founded on March 1, 1942, after President Franklin D. Roosevelt withdrew an initial 126,720 acres of Utah land from the public domain for use by the War Department.