Los Angeles schools have been closed as an unspecified threat is investigated, police have said.
The district is the second largest in the US, with 640,000 students attending more than 1,000 schools.
Burbank, Glendale, Compton, Santa Monica, Pasadena and San Bernardino remain open.
New York City officials said they were also threatened and says it isn’t credible.
Gay superintendent Ramon C. Cortines in LA says it is