Two Irvine schools briefly went into lockdown Friday when a teacher mistakenly thought she saw someone wearing a mask on campus, according to a statement posted by the Irvine Unified School District.

University High School and Turtle Rock Elementary School were locked down for about 10 minutes at 11:30 a.m. while police searched from the air and ground before clearing the area of any danger, University Principal John Pehrson said in a message to parents.

At no time were students in danger, according to Pehrson. The incident was sparked when a teacher saw a student delivering a package from one teacher to another at University and mistook him for a threat.

"The student happened to be walking with his head down and apparently had his hair or hoodie covering much of his face. Another teacher saw this student, and at quick glance, thought that the individual had a mask on," he wrote.

Police quickly confirmed the student with the package was what the teacher saw.

"These days we are taking every precaution...." Pehrson wrote. "If nothing else, it was an opportunity for a very realistic drill."

— Jeremiah Dobruck

Twitter: @jeremiahdobruck