A man was handcuffed and led off a plane in Honolulu on Friday after passengers restrained him and fighter jets escorted the flight to the airport.

Before he even boarded the plane, Anil Uskanli had been arrested by police at Los Angeles International Airport after a worker allegedly spotted him walking through a security door leading from the terminal to an airfield ramp shortly before 3 a.m Friday. He was released after being charged with a misdemeanor, police said. The 25-year-old had been drinking, airport police explained in a statement, but wasn’t drunk.

He later boarded American Airlines Flight 31, but looked disheveled and “clearly out of place,” passenger Donna Basden told the Associated Press.

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Basden said that when she and her companion sat down in their first-class seats, they found a laptop computer in the seat-back pocket. A flight attendant said the computer probably belonged to a man had left it there and gone to the bathroom, according to Basden.

Uskanli retrieved the laptop — scowling, Basden’s companion said.

Uskanli reportedly tried to then sit in a different first-class seat, but he was eventually directed to his seat at the back of the plane.

Halfway through the flight, about 9:30 a.m., according to an FBI agent, Uskanli again appeared in the front of the plane with his laptop. This time, passengers said, had a towel or blanket over his head.

“He was very quiet, moving very sluggish,” passenger Grant Arakelian said, according to the Associated Press. “He was trying to approach the cabin, like where the captain is.”

Uskanli’s intentions were unclear, an FBI agent later told reporters. But intelligence officials have been on alert after warnings of possible terrorist group efforts to hide bombs in laptop computers and other electronic devices. Laptop computers have been banned from carry-on baggage on many U.S.-bound flights from the Middle East, and they may soon be banned on flights from Europe.

A flight attendant ran down the aisle with a beverage cart, using it to block Uskanli from the front of the plane.

“She jammed the cart in the doorway and she just said, ‘You’re not coming in here,'” passenger Lee Lorenzen told the Associated Press.

Lorenzen was among several passengers, including an off-duty police officer, who tried to restrain the man.

“He was pushing against the cart, and a bunch of guys grabbed him,” he told Hawaii News Now. “They found some duct tape. There were pillows and blankets. And they taped him to his chair.” American Airlines later denied the man was restrained with tape.

Reports of Uskanli’s behavior on the plane prompted two F-22 Raptor fighter jets to scramble. The escort was in accordance with security procedures, a Navy commander told CNBC.

After the plane landed in Honolulu, a passenger took video of FBI agents leading Uskanli, a Turkish national, off in handcuffs. Agents and police dogs then searched every seat and passenger.

First look of suspect, 25-year-old Anil Uskanil being escorted off American Airlines flight #31 by the FBI. #honolulu pic.twitter.com/QqGbd2IwAY — Shanell Wolslagel (@SJWolslagel) May 20, 2017

The cockpit was never breached, and bomb technicians found nothing threatening in Uskanli’s possessions, according to the FBI. He was taken for medical evaluation and faces a complaint for interfering with a flight crew.

The Department of Homeland Security is involved in the investigation, and agency officials said all U.S. flights would be monitored after the incident, “out of an abundance of caution.”

American Airlines did not provide more information on the incident, and it was unclear if Uskanli has a lawyer. The FBI did not respond to questions, and it was unclear if Uskanli was still detained.

Correction: The Associated Press originally reported that the passenger’s last name was Uskanil. It has since corrected that to Uskanli. This story has been corrected.

The Associated Press and other outlets initially reported that the Uskanli was duct-taped to his seat, citing a passenger’s account. Since then, American Airlines has denied the was taped down, and suggested early accounts of the incident confused a security procedure in which his laptop was barricaded and taped in place in case it contained explosives.

This post has been updated.

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