The evacuation drill happened at ECU’s Pediatric Specialty Care Clinic on Herbert Court in Greenville.
Employees were told there was an armed individual outside the building just before 1 p.m. on Friday afternoon.
A voice message system then told the staff to go into lockdown mode.
Within minutes, officials said officers were inside the building and were escorting employees to the ECU Women's Clinic next door.
NewsChannel 12 talked with Lt. Chris Sutton about the importance of the drill.
"We did not have a person that was set up in a role playing situation but even knowing that, even going through the drill, it still created some stressful moments for [the employees]," Sutton said.
Police said performing test case scenarios allows them to figure out what works and doesn't work.
Officials had two other staging areas on campus. One was held on the health sciences campus to handle communications. The other was on the East campus.