The Dallas Office of Emergency Management held a drill exercise for a mass casualty event in downtown Dallas Sunday.
It started at 8 a.m. at the Majestic Theater 1925 Elm St. to imitate a stage collapse.
Elm Street was closed as 300 personnel and over 700 volunteers worked the exercise.
Volunteers were dressed in fake blood and white shirts, which had their condition written on the back, such as "bleeding from scalp."
“This large-scale exercise helps our responders be better prepared in the face of an actual event,” the Dallas Office of Emergency Management said in a Facebook post.
"It’s extremely important that these types of drills we run are more focused on agency capabilities, because the bottom line is we can’t accurately predict every aspect of an emergency incident when it happens," Dallas Fire-Rescue spokesman Jason Evans said.
Twenty-five different agencies were involved, including Dallas Fire-Rescue, Dallas Police, as well as Methodist Dallas, Parkland, Baylor, Texas Health Presbyterian and Children’s Hospitals.
Elm Street has since reopened.