Two people have been arrested in connection with the drone incident that paralyzed London’s Gatwick Airport for more than a day, local officials say. Only few details were immediately released.

Both suspects were arrested just after 10 p.m. local time on Friday on suspicion of criminal use of drones. There was no immediate word on their identities, where they were arrested, or how they were found.

“Our investigations are still ongoing, and our activities at the airport continue to build resilience to detect and mitigate further incursions from drones, by deploying a range of tactics,” said James Collis of Sussex Police.

“We continue to urge the public, passengers and the wider community around Gatwick to be vigilant and support us by contacting us immediately if they believe they have any information that can help us in bringing those responsible to justice,” he said.

Collis added: “The arrests we have made this evening are a result of our determination to keep the public safe from harm, every line of enquiry will remain open to us until we are confident that we have mitigated further threats to the safety of passengers.”

Gatwick Airport was shut down on Wednesday night when drones were illegally flown near the runway. The drones returned multiple times, causing hundreds of flights to be canceled and impacting more than 100,000 travelers.

The airport, one of the busiest in Britain, re-opened on Friday morning. A motive for the disruption is still unknown, but police have said they do not believe it is related to terrorism.