WASHINGTON — A flight to San Francisco was disrupted Sunday when law enforcement officials reportedly boarded the plane as soon as it touched down to arrest one of the aircraft’s pilots. 

Multiple outlets reported about the incident on board a domestic Delta flight, which was first detailed by the San Francisco Chronicle. 

The pilot, whose identity wasn’t immediately released, was arrested on charges relating to child sexual abuse material, an official with the Department of Homeland Security said Monday.

According to the Chronicle, a group of federal agents suddenly boarded the plane after it landed and stormed the cockpit. 

“A group of people with badges, guns, and different agency vests/markings were pushing their way up through the aisle to the cockpit,” a passenger wrote in an email to The Chronicle.

A witness told ABC7, a San Francisco-based TV station, that at least 10 agents boarded just as passengers were beginning to unload their bags. 

“I don’t know if this person was disappearing before our eyes, if there had been a crime committed, or what exactly was happening,” the witness, who asked not to be identified by her full name, said. 

The woman told ABC7 that everybody on board, including the remaining pilot, was confused by the sudden incident. 

“It was scary. It was traumatic to watch,” she said. “As soon as my husband picked me up from baggage claim, I jumped in the car and cried. Because who knows what’s happening to that poor person? Why that happened? What did we just see?”

The pilot who was arrested has not been publicly named, and its unclear which federal agencies were involved in the arrest. 

Video of the incident, posted by View From the Wing, an airplane-focused news outlet, appears to show plainclothes law enforcement officers walking out of the cockpit with badges displayed. 

Plainclothes officers conducting arrests has become a hallmark of Immigration and Customs Enforcement, or ICE, under President Donald Trump. 

But in the video, a person appears to say, “this isn’t immigration.” 

The plane was flying into the San Francisco International Airport from Minneapolis when the arrest happened. It landed late, around 9:35 p.m. Pacific, after being delayed on approach because of heavy fog in the San Francisco area.