Classes were cancelled Tuesday through Friday at Mater Dei High in Santa Ana following what school officials call a credible threat.
Santa Ana Police confirmed that officers on the campus determined there was no threat of a shooting. The Roman Catholic Archdiocese of Orange chose to shutdown the school as the investigation continues.
Police aren't saying exactly how or when the threat to Mater Dei was received or why they think a former school employee is the source.
Campus leaders alerted parents Tuesday afternoon by saying: "Safety and sweep protocols were implemented. We acknowledge the alarming nature of this message; however, we at Mater Dei take all threats made to the school seriously."
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Neighbors welcome the choice made by the Diocese of Orange to close Mater Dei temporarily.
"Any kind of threat like that you should probably shut down the school and maybe get some armed guards," said parent Manuel Perez.
Maritza Silas, another parent, says she's scared to drop off her kids at school.
"I know it's something that I have to do," she said. "But it is scary."
Julio Lugo, a parent, says it's the right thing to do.
"Anything that can be done to save lives," he said.
Matthew Vu, a resident, says the Texas elementary school massacre is on his mind.
"I do have a little sister, graduated high school," he said. "Hear about those type of stories, I imagine my little sister. It kind of hurts."
Maritza, a mother of five, believes Mater Dei has the right idea: to minimize risk as families counsel children on keeping safe in class.
"Already had in school," she said. "It's really sad for me to have that conversation with them. I know I'm gonna have to. They already know to run away or hide. They know what they're going to do if that happens."
For the last days before school is out for summer, the school is figuring out distance learning arrangements.
"We are committed to providing timely updates and appreciate the parents' and students' understanding as we work diligently to ensure the safety of our community at all times," the school said.
The last day of school before break is June 9.
On May 24, an 18-year-old gunman opened fire on a Uvalde, Texas, elementary school, killing 19 children and two teachers and injuring many more in their last week of school before the summer break. Since then, disturbing details have emerged, and schools across the nation have seen students staging walk-outs over gun violence.