A campus-wide, building-to-building sweep of the school grounds lasted four hours.

St. Paul Police patrolled the wooded area on campus where the 25-year-old guard, Brent Patrick Ahlers, said he’d been attacked. They set up a perimeter around St. Catherine’s and conducted an “exhaustive” search, with 55 officers, four police K-9s, and a Minnesota State Patrol aircraft circling overhead.

Highland Park residents wondering what all the ruckus was about tuned in to the police scanner. As tweeted by one regular scanner listener, they heard the suspect described as a "black male" wearing a navy blue sweatshirt, black jeans, and a short afro.

Again suspect is a black male, navy blue sweatshirt with the word "Navy" on it., black jeans and a short afro. #StCatherine #StPaul — Julie (@wwozzydo) September 13, 2017

“The idea there were all these cops swarming around, looking in alleys and looking for a black male … everyone was so on edge and high-alert,” says neighbor Lisa Clark.

Police did not locate a suspect, however, and called off the search just after midnight, leaving the cops and campus to worry about an armed and dangerous suspect on the loose.

The next night, Ahlers came clean: The only active shooter on Tuesday was him.

He’d actually shot himself by accident while handling a gun he wasn’t supposed to have on campus. He told them he lied because he was afraid of losing his job. Ahlers was arrested and jailed for falsely reporting a crime, a misdemeanor, according to the St. Paul Police, who also confirmed Thursday that Ahlers' call for help had reported a "black male" as the man who shot him.

“When someone taps into realistic public shootings, things that seem to pop up too frequently, it’s a real concern that people have,” says Clark, echoing reactions that proliferated on a Highland Park neighborhood Facebook group Wednesday night.

“I was angry that he subjected the entire neighborhood to this huge police presence, that people were afraid being out and about … and that he took it past that, into tapping into people’s racism.”