The Los Angeles Academy Middle School was locked down just before 3 p.m. on Tuesday, the LA School Police Department announced on Twitter.
The Los Angeles Police Department said they received a call about a threat phoned into the school just before 1:30 p.m. No details about the threat were immediately available.
The LASPD is taking the lead in the case, and both LASD and LAPD officers are at the school.
"A parent/student reunion gate is located at Avalon Blvd/ E 56th St.," the LASPD announced on Twitter.
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Police said the lockdown was lifted just before 4 p.m., but no additional details were provided.