NATCHEZ — Emergency personnel Tuesday responded to what was “just a drill,” but their strictly business demeanor could have fooled the unsuspecting onlooker.

From approximately 9 a.m. to 2 p.m., police officers, firefighters and EMTs took part in an emergency drill, which involved a car wreck involving an overturned car, another vehicle containing sulfur dioxide and an active-shooter situation at Merit Health Natchez.

“We combined two exercises into one,” Adams County Emergency Management Director Robert Bradford said.

From start to finish, the emergency personnel acted as if the scenario was actually unfolding.

Natchez Police Captain Tom McGehee said the first phase of the drill consisted of the wreck off Liberty Road at the National Guard Armory.

At the scene of the wreck, police had the area blocked off, as American Medical Response ambulance workers removed victims.

Simultaneously, the Natchez Fire Department tended to the sulfur dioxide, a toxic chemical compound, which Bradford said the first portion of the drill aimed to test. Natchez Fire Department Operations Manager Conner Burns, who was the public information officer for the drill, described the firefighters’ role in the “accident.”

“We’ve determined the material (we are dealing with) is sulfur dioxide,” Burns said during the drill. “We’ve evacuated everyone within .4 miles around the scene.

“We’re assessing the scene. We could be dealing with potential loss of life, but we can’t confirm that right now.”

The drill then moved to Merit Health Natchez, where emergency responders transported the victims for treatment.

Merit Health Natchez spokeswoman Kay Ketchings, while still participating in the drill, said personnel relayed news of the wreck to the hospital as doctors prepared for the victims to arrive.

“We’re expecting eight patients, but there could be more,” Ketchings said.

Suddenly, a simulated gunshot rang out in the hospital’s emergency bay, as the training demonstration evolved into an active shooter scenario.

Within five minutes, three Natchez police cars swerved to block the path into the hospital parking lot, as three officers toting fake weapons tactically approached the scene.

Merit Health personnel said the hospital would be locked down in such a scenario, but one woman walking to her car seemed to be convinced by the policemen’s performance.

She froze as the officers ran by but gave a nervous laugh once hospital workers told her, “You’re OK, it’s just a drill!”

Bradford said this was his first experience running an exercise that combined two different emergency scenarios.

“It went well,” Bradford said. “There are some areas we’ve got to improve on … we’ll rehash those and probably come back next year and run another (drill).”

When identifying areas for improvement, Bradford identified communication as the main priority.

“Communication will be number one — working on our communication from dispatch … to our Emergency Operations Center, and also being able to talk to the hospital during events of this caliber.”

Bradford said these drills, formally known as “community multiple hazard full-scale exercise,” help emergency workers to refine logistic plans regarding personnel and equipment.