The reason for the nationwide disruption, which lasted several hours, stemmed from software changes made in late December, according to U.S. Customs and Border Protection (CBP) officials.
“Initial investigation into the cause indicates that the problem was due to changes made to the software used to process travelers on Dec. 28. Those changes were bypassed to resolve the issue,” the statement read.
In the major air travel hubs like Miami and Chicago, travelers reported their frustrations and the human logjams that resulted via social media.
@cnnbrk please let US Customs know the Miami airport could use a little help. Thousands of us waiting in a "line". pic.twitter.com/VGLUOUiaoP — Garret Prather (@garretp) January 3, 2017
The agency responsible for vetting travelers and goods crossing U.S. borders said via its Twitter feed that the incident did not appear to be malicious.
All airports are back on line after a temporary outage of #CBP’s processing systems. No indication the disruption was malicious in nature. — CBP (@CustomsBorder) January 3, 2017
But this incident is not the only inconvenient outage in recent memory. In October 2015, the agency experienced a 90-minute system disruption linked to the computers and kiosks that process incoming travelers against the national terror watch list, according to Time magazine.
In both cases, authorities were forced to vet passengers manually until the systems were brought back online. Despite the long lines, the CBP said all passengers were subject to equally stringent security screenings.
"During the technology disruption, CBP had access to national security-related databases and all travelers were screened according to security standards," the agency said.