Airports in Long Beach and Orange County were shut down early Tuesday because of bomb threats, officials said.
Bomb threats were made by telephone, according to Long Beach airport spokeswoman Sharon Diggs-Jackson and federal Transportation Security Administration spokesman Nico Melendez.
At Long Beach, all early flights were canceled, said police Nancy Pratt. Police were searching the airport with bomb-sniffing dogs.
Officials cautioned that even after the airport was reopened there would be long delays because screeners would have to check a large volume of passengers.
John Wayne Airport in Orange County reopened and resumed normal operations, Melendez said.
Both airports are located within 50 miles of Los Angeles.