Authorities on Thursday were investigating reports of an unspecified threat at Santa Ana High School.
The Santa Ana Police Department announced about 1:35 p.m. that units had responded to the school, located in the 500 block of West Walnut Street.
The school was placed on lockdown out of abundance of caution as authorities investigated the threat.
“No one is currently allowed in or out of the campus to help ensure the safety of our students and staff,'' Santa Ana High School said in a statement.
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“Please know that student and staff safety is always our top priority,'' the statement said. "The Santa Ana Police Department and Santa Ana Unified School District Police Department are on site responding to the incident. Students are safe and all security protocols are being followed."
Police could not immediately confirm the nature of the threat, but ABC7 reported police responded to the school on "reports of a possible bomb threat and a potentially armed person on campus."
Authorities were on scene investigating the threat as of about 2:45 p.m., and the public was advised to avoid the area.