A four-hour outage for U.S. Customs and Border Protection left throngs of angry passengers dealing with significant delays from South Florida to Boston to Los Angeles for several hours Monday afternoon and evening.
Customs and Border Protection, or CBP, said the "technology disruption" began about 5 p.m. ET and was resolved by 9 p.m. All airports were back up and running late Monday, CBP said.
"At this time, there is no indication the service disruption was malicious in nature," the agency said.
Passengers on more than 30 international flights were affected in Miami, an airport official told NBC Miami. One traveler told the station that two people passed out waiting in line.
Travelers took to social media to post photos and videos of the long lines and annoyed customers.
The list of airports included: Miami International, Fort Lauderdale/Hollywood (Florida) International, Hartsfield-Jackson Atlanta International, John F. Kennedy International (New York), Logan International (Boston) and Los Angeles International.
A similar but briefer failure occurred in October 2015. Customs officials blamed that episode on problems with the computers and kiosks used by passengers arriving in the country.