Los Angeles police spokesman Andy Neiman said today that the reports were spurred by loud noises only, and police are still investigating to find the source of them.
The reports caused people to pour on to sidewalks and out on to the tarmac at the airport.
Later, people could be seen walking back into the airport and flights starting to take off again.
Earlier, police said they were searching the terminals and social media posts showed many people fleeing Los Angeles International Airport amid rumours of a possible shooting.
Scores of people could be seen on social media and on TV news running from the terminal out on to the sidewalks and streets.