Onboard 'Verbal Disturbance' Prompts F-16 Fighter Jets to Escort Diverted Delta Flight to Tucson

— -- A Los Angeles-bound Compass Airlines aircraft operating on behalf of Delta Airlines was diverted to Arizona's Tucson International Airport Wednesday afternoon, following an onboard "verbal disturbance" involving a passenger, the FBI and Tucson Airport Authority confirmed.

NORAD confirmed to ABC News that it scrambled two F-16 fighters to intercept the jet, which was carrying 80 people, including passengers and flight crew. The plane's flight crew notified the captain and copilot of the disturbance, leading to the F-16 fighter escort. The NORAD spokesman did not have details on the disturbance itself but said whatever it was met the criteria to launch the fighters, which monitored the plane until it landed in Tucson. Citing “operational security”, they won’t say where the F-16s launched from.

A source tells ABC News one passenger accused another passenger of having a firearm, but when the aircraft was swept and passengers re-screened, no weapon was found. According to another source with knowledge of the investigation, the passenger reported to have a firearm was detained, but authorities later discovered he did not have a weapon on him. The man had a history of mental illness, the source said.

The Embraer 170 aircraft was was en route to Los Angeles International Airport from San Antonio, Texas, according to the FAA.

The Tucson Airport Authority Police confirmed that one of its uniformed officers escorted and handcuffed the suspect along with an FBI agent, who took the individual into federal custody because of the "verbal disturbance," a spokesperson told ABC News. All passengers were taken off the plane and re-screened by TSA.

The FBI's Phoenix office said it was investigating the incident, but said there was no threat to public safety. They declined to tell ABC News if the suspect was in jail, a hospital, or has been released as of Thursday morning.

The FAA identified the aircraft as Compass flight 5720; it landed without incident at 4:35 p.m. PT.

One the passengers on the plane, Ryan Healy, tweeted a series of photos, video and posts detailing how FBI agents entered the plane's cabin and removed the individual, and how the plane was escorted by fighter jets.

Tucson Airport sent out a series of tweets, beginning at 5:37 p.m., the first of which read, "There was an incident on a flight was a diverted to @tucsonairport. 1 suspect detained at this time. Aircraft deemed safe."

Two minutes later, Tucscon Airport tweeted, Passengers on diverted flight @tucsonairport and are being transported to terminal for rescreening."

A subsequent tweet, only a minute later, classified the diversion to Tucson Airport as a result of "interference with flight crew."

Less than half an hour after its first tweet, Tucson Airport said "Passengers are currently being re-screened. They will then continue on to their final destination."

ABC News' Joshua Hoyos, James Meeks, Jonah Lustig and Erin Dooley contributed to this report.