Officials briefly evacuated an elementary school in Costa Mesa after an anonymous bomb threat was called in Wednesday morning, according to police.

Fire and police personnel started ushering students and adults off campus at California Elementary School, 3232 California St., around 11:15 a.m., Costa Mesa police Lt. Mark Manley said.

By 11:40 a.m., students were headed back to class.

"We did an assessment of the area and made sure it was clear," Manley said.

As a precaution, nearby TeWinkle Middle School was placed on lockdown, according to Laura Boss, a spokeswoman for the Newport-Mesa Unified School District.

"The schools have been cleared by the Police Department and the threat was determined not to be credible," Boss said in a statement. She said officials would notify parents of the incident.

— Jeremiah Dobruck

Twitter: @jeremiahdobruck