While Phoenix Police Department cars patrol Carl Hayden High School's perimeter, parents began asking why the school district's administration didn't alert them sooner to a threatening message found in a school bathroom early this week.
The school was not allowing students to bring backpacks to the school near 35th and Roosevelt Street on Friday and told students that all Valentine's Day presents would be secured in an office until after school.
Some parent said the schools' response should have started Tuesday.
A Carl Hayden High parent, who asked to be identified as Miss G, said she isn't second-guessing a threat of violence.
"He's not coming to school tomorrow, definitely not," Ms. G said of her son.
Officials first learned of the threat Tuesday when a school resource officer discovered a note in a bathroom on campus.
"The particular note did describe something that was going to occur," Phoenix police Sgt. Steve Martos said.
But Phoenix Unified School District officials decided not to notify parents right away.
"If we're supposed to work together as a team, they have to let us know and they didn't even send a letter until today," Ms. G said.
"Right away you have to let parents know, (then) we decide to bring or child back to school or not," she said.
School district leaders declined requests for an interview with CBS 5 News.
But in a phone call late Thursday afternoon, district spokesman Craig Pletenik said the district needs to "be more immediate about threats on social media."
"The district investigates threats all the time, quietly," he said.
Pletenik said the district didn't want to create hysteria with the Carl Hayden threat.
But he also admitted the district needs to be more proactive with its communication and getting out in front of issues.
Martos said there would be a dramatic increase in security precautions Friday.
"We are going to have some resources available to us, and the school has also taken some steps," he said.
Police and school officials were still trying to track down the origin of the threat.
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