Passengers are starting to be processed at airports in the US Friday evening after an hours-long slowdown caused by a customs computer glitch.

"The affected systems are coming back online and travelers are being processed. CBP will continue to monitor the incident. There is no indication the disruption was malicious in nature at this time," CBP said.

Several airports said that US Customs had to process passengers manually and using backup systems, causing the slowdown.

"CBP systems are experiencing an issue which appears to be impacting multiple airports including LAX. Officers are processing passengers manually so please check with your airline for the latest status of any flight impacts. More details as they become available," LAX tweeted Friday afternoon.

"Customs systems are down right now nationwide but they are starting to use backup systems. People are being processed, but slower. Thanks for your patience," JFK Airport tweeted.

Twitter users shared photos of long lines at various airports throughout the nation.

@JFKairport this is a joke. pic.twitter.com/CBuW6ZgypG

— FrankCesario (@fcesario01) August 16, 2019