After six hours of searching, police did not find a gun at the school, officials said. However, that news did little to calm parents and students who said the incident is another example of rising tensions in the high school.
The day started with a phone call to Harding's office, saying there was a gun on campus.
Harding student Quanif Johnson said they spent the day locked in one classroom watching officers and police dogs go room-by-room, looking for a weapon.
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"They searched your bag, your pants, everything," he said.
Outside, parents waited, unable to pick up their children. One parent, who was among the first to arrive after reports of the gun surfaced, said she may not let her daughter come back to the school.
Her daughter joined her after school, wiping tears from her eyes. "A lot of things have been taken away from us, because of all the stuff we have to go through," the girl said.
D'Arrea Hemphill, a senior at the school, blamed the incident on the school district's decision to move former Waddell High School students into Harding.
"Every day is fights," Hemphill said.
Parents and other students are also coming to that same conclusion.
One mother said her daughter deserves better.
"She's here to get an education. I don't know what all these other children are trying to do, but she is here to get an education. And those who don't want one need to move on," she said.
District police are still investigating the gun threat, but they said it is too early to comment on issues stemming from new students at the school.
"I loved this school before this year. Now, I don't want her here," said another parent.
Police would not go into detail about the anonymous call, just saying they take every threat seriously.
However, police did say they found some knives and other weapons during their search.