The lockdown of the base in Flowood, a Jackson suburb, also prompted Gov. Phil Bryant to return from an event on the Mississippi Gulf Coast and sent area law enforcement officers and first responders rushing to the scene.
A Madison police officer assigned to a federal task force was in a car accident on the way to the base, but was not seriously hurt, said Madison's assistant police chief, Robbie Sanders.
Adding to the confusion, the 172nd Airlift Wing had been preparing for a drill this week that would have simulated a gunman on the base.
The unit is near the Jackson-Medgar Wiley Evers International Airport and uses the airport's runways.
Tim Powell, a Guard spokesman, said the airport uses a firing mechanism that makes noise to scare away birds.
Birds are hazardous to aircraft. Perhaps the most well-known bird strike in the United States happened in 2009 when a flock of geese brought down US Airways Flight 1549 and the captain safely landed the jet in the Hudson River.
Powell said someone thought the noise was a gun and reported it to the command center, which prompted the lockdown.
Airport CEO Dirk Vanderleest said the device is similar to a starter pistol and fires something like a bottle rocket.
Vanderleest said the airport uses the device often and it hasn't caused a problem before. He said "heightened awareness" due to the upcoming drill likely contributed to the situation.
Powell said Guard commanders were pleased with the way the unit and civilian authorities responded to what they believed may have been a dangerous situation.
"Everybody responded correctly. Law enforcement responded very, very quickly," Powell said. "It's obvious the plan is working correctly. And that's the kind of plan that would save lives."
The governor returned to Jackson and went to the base after learning there were reports of gunfire, according to his spokesman, Mick Bullock.
"The governor received a call and took that call very seriously and responded appropriately," Bullock said.
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