Officials at South Ridge High School canceled classes Monday after a "vague" remark from one student last week spread and escalated over the weekend into a perceived threat against the school.
Phoenix police spokesman James Holmes said officers received information on Friday afternoon about a possible threat against the school.
A student "indicated in a very vague manner" that students should avoid coming to school, he said. Over the weekend, students shared that remark and the rumor evolved into a perceived direct threat against the school.
Police spoke with students and parents over the weekend and determined the threat to be not credible.
"Over the weekend there was speculation regarding an alleged threat to our campus. Police have determined the alleged threat to be non-credible and a rumor. We take any and all threats seriously, and as such, we initiated our immediate response protocols," said Melissa B. Rivers, school leader at South Ridge High School.
Rivers said school will be back in session on Tuesday.
"While this is an unexpected disruption to our learning environment, the safety and security of our students and staff is at the forefront of all we do," she said.