Airlines in the United Kingdom faced continuing disruptions on Wednesday as they worked to manage a significant backlog of canceled and delayed flights caused by technical problems in the country’s air traffic control system. The issues, which first arose Tuesday, compelled the cancellation of more than 2,000 flights and led to extended delays across 15 airports nationwide.

Passengers encountered lengthy waits both on airport runways and in terminals as the disruptions persisted into a second day. Airlines and airports undertook efforts to rebook travelers and reposition aircraft that had been misplaced due to the cancellations, but delays were expected to continue throughout Wednesday.

NATS, the organization responsible for operating the U.K.’s air traffic control system, attributed the initial disruption to a problem in its flight processing system. While the technical fault was resolved by Tuesday afternoon, NATS indicated that the ripple effects were ongoing and that it was working closely with airlines and airports to support recovery efforts.

The incident underscores vulnerabilities in the aviation infrastructure and the challenge of restoring normal operations following a major systemic failure. Authorities emphasized their commitment to minimizing further disruption and ensuring safe and efficient management of air traffic as services return to regular schedules.