MINNEAPOLIS - About 1,300 workers spent two midday hours locked inside the Retek Building in Downtown Minneapolis, as SWAT and K-9 units went room-by-room and floor-by-floor.
The call from Target Security came in as shots-fired around 11 a.m.
"When we get a call of shots fired we're going to respond," acting Minneapolis Police Chief Janee Harteau said.
Dozens of anxious people stopped by to take a look, noticing the nine squad cars in front of the buildng on 10th Street South.
Meanwhile, the hundreds of workers inside, waiting for an "all clear" took to texting and social media.
"It's going to take as long as it takes to make sure the building is safe," Sgt. Steve McCarty warned reporters when asked how long the search would take.
Two hours after that initial call, the acting Police Chief addressed reporters.
"There is no evidence of a shooting of any kind," she noted, before admonishing several rumors that had circulated over the lunch hour.
Lt. Richard Zimmerman explained where the "gunshot sound" may have come from.
"The only explanation is it would be duct work or something in the ventilation system," he said.
Police say the person or people who called security after becoming alarmed by the loud noise did the right thing. Police later determined that the noise likely came from a construction worker's tool that mimicked the sound of gunshots.
They were merely erring on the side of caution. Police were too.
"When we get a call of shots fired we're going to respond. We didn't have evidence that there was or wasn't. Until we can disprove something occurred we have to be really thorough," Harteau concluded.
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