Travelers flying into the United States on Friday ran into long lines at major airports nationwide because of a temporary computer outage that affected the U.S. Customs and Border Protection agency.

Airports warned travelers — both Americans returning home and foreign visitors — of delays, and some travelers tweeted photos and videos of huge lines.

Inbound international flights to Daniel K. Inouye International Airport on Oahu and Ellison Onizuka Kona International Airport on Hawaii island may be affected, the state Department of Transportation announced in a tweet.

Hawaii DOT officials tweeted just after noon that the Customs’ systems at the two airports “are operational however there are delays processing incoming international flights. Expect delays if you are picking up international passengers.”

The #CBP systems at #HNL and #KOA are operational however there are delays processing incoming international flights. Expect delays if you are picking up international passengers. Follow @CBP on Twitter for updates. Mahalo for your patience.

— Hawaii DOT (@DOTHawaii) August 16, 2019

“CBP is experiencing a temporary outage with its processing systems at various airports of entry & is taking immediate action to address the technology disruption,” the agency said in a tweet. “CBP officers continue to process international travelers using alternative procedures until systems are back online.”

CBP is experiencing a temporary outage with its processing systems at various air ports of entry & is taking immediate action to address the technology disruption. CBP officers continue to process international travelers using alternative procedures until systems are back online.

— CBP (@CBP) August 16, 2019

Jamie Ruiz, of CBP, said in an email sent to the Star-Advertiser at about 1 p.m. that the affected systems were coming back online and travelers were being processed accordingly.

“CBP will continue to monitor the incident,” Ruiz said. “There is no indication the disruption was malicious in nature at this time.”

A CBP spokeswoman said the systems were running again by early evening on the East Coast.

The agency didn’t precisely describe the breakdown, but the spokeswoman said there was “no indication of any nefarious activity.” She said officers were able to access security-related databases and maintain security standards while screening people manually.

Rebekah Tromble, an associate professor at George Washington University, tweeted a video clip in which she panned over the arrival hall at Dulles International Airport in northern Virginia. She estimated there were at least 5,000 people packed into the hall.

Tromble was asked if she could see whether customs agents were screening people manually.

“It’s not clear from my vantage point. I’m still too far back in line,” she answered.

Airports in Los Angeles, Dallas-Fort Worth, New York and elsewhere notified travelers of potential delays at the beginning of one of the last weekends of the summer vacation season.

The port authority that operates New York’s JFK Airport and the airport in Newark, New Jersey, said additional staff and police officers monitored situation and helped where needed. Los Angeles International Airport said it sent staffers to CBP areas to help direct travelers.