American Airlines said in a statement that law enforcement met the plane upon landing in Honolulu following the "disturbance" on the flight. The plane was escorted by two F-22 fighter jets for the duration of the flight following the disturbance, U.S. Pacific Command said in a statement.
Special Agents of the FBI Honolulu Field Office and local police responded ahead of the flight’s arrival and took a passenger into custody. The Department of Homeland Security is continuing to monitor all flights "out of an abundance of caution," it said.
About halfway through the flight, the passenger, identified as 25-year-old Turkish national Anil Uskanil, was headed towards the front of the plane. He had a blanket over his head and was mumbling, witnesses said.
It’s unclear how far towards the front of the plane he made it. Some eyewitnesses told ABC News that he tried to push his way through first class to the bathrooms, but was blocked by the beverage cart and a passenger.
Earlier on Friday, a source at the TSA told ABC News that the passenger was waiting for the bathroom near the cockpit when a flight attendant asked him to sit down. He had a laptop with him and appeared to try the cockpit door before he was subdued, the source said.
American Airlines has stated that he was "moving towards the cockpit."
But Paul Delacourt, special agent in charge at the FBI's Honolulu office, confirmed Friday night that the cockpit was not breached, nor did Uskanil even make it to the cockpit door.
After the disturbance, Uskanil was escorted back to his seat, where he was restrained with duct tape, according to witnesses. At no time during the incident was there any violence or significant struggle, witnesses said. He was later taken into custody for a medical evaluation.
LAX Police told ABC News that at 2:45 a.m. they received a radio call of a passenger moving through a Terminal 5 security door, which led to the airfield ramp. Uskanil, a ticketed passenger on an American Airlines flight who had passed through TSA security, was detained after being spotted. Police determined he had been drinking, but did not meet criteria for public drunkenness. Uskanil was arrested for misdemeanor trespassing, cited, given a pending court date, then released from custody.
American Airlines says Uskanil then went back thru a TSA checkpoint in Terminal 4 where his flight to Honolulu was leaving from and boarded the flight. The airline also says that he had bought his ticket for the Honolulu flight shortly after midnight at the airport ticket counter.
Law enforcement is now responding to analyze a suspicious item associated with Uskanil, a source told ABC News. The FBI's Delacourt, though, said no explosives were found onboard.
Flight 31 from Los Angeles landed safely at 11:35 a.m. local time, according to American Airlines. All passengers are off the plane and safe, and operations at the airport have resumed as normal.
A total of 181 passengers and six crew members were on board, according to the airline.
The incident is under investigation. Halting of all ground movements on the airfield as the flight came in caused a 30-minute backlog, the Department of Transportation said in a statement. The DOT expected the backlog to be resolved by the end of peak travel in the afternoon.
ABC News' Matt Gutman, Erin Dooley, Luis Martinez and Alex Stone contributed to this report.