A pilot for Delta Air Lines was arrested in the cockpit of a plane just moments after it landed at San Francisco International Airport on Saturday night, the authorities said, with the crew and passengers still on board as agents led the pilot away.

The Department of Homeland Security confirmed in an email on Monday that it had arrested a pilot at the airport on charges involving child sex abuse materials. It did not give any further details about the pilot or the charges.

Flight 2809, a Boeing 757-300, arrived in San Francisco at 9:35 p.m. on Saturday after departing from Minneapolis, with heavy fog around the San Francisco airport delaying its landing by a few minutes.

A passenger on the plane told the San Francisco Chronicle that several people with “badges, guns and different agency vests/markings” made their way up the aisle and into the cockpit, where they put one of the pilots in handcuffs and escorted that pilot off the plane.

The passenger estimated that there were at least 10 law enforcement officers involved in the arrest.

The aviation blog View From the Wing published a short video showing several people with visible badges walking out of the plane’s cockpit.

Delta declined to comment on the arrest and directed questions to law enforcement agencies.