United Airlines delays 150 passengers overnight following serious in-flight threat

A disruptive passenger forced a Newark-bound United Airlines flight to make a swift U-turn back to Las Vegas late Saturday night, grounding the cross-country trip until Sunday morning. United Flight 1681 had just departed Harry Reid International Airport when the crew flagged "a potential security concern" in the cabin. The Boeing 737, carrying 150 passengers and six crew members, safely touched back down in Vegas at roughly 11:05 p.m. without any reported injuries, several news outlets reported. TRAVEL NIGHTMARE UNFOLDS AS MAJOR AIRLINE SCRAPS FLIGHT AFTER HARROWING 12-HOUR DELAY "United flight 1681 from Las Vegas to Newark on Saturday, Oct. 24, safely returned to Las Vegas to address a potential security concern," United Airlines said in a shared statement with Fox News Digital. "The flight was delayed overnight due to crew timeout, and departed for Newark this morning," the statement continued. While the midair scare was resolved without physical harm, the diversion triggered an overnight delay after the flight crew timed out of their legally permitted working hours. Fox News Digital reached out to the Department of Homeland Security (DHS) for comment. In an air traffic control audio recording that ATC.com obtained, a controller can be heard asking pilots if a passenger in question was "compliant or restrained." CLICK HERE TO SIGN UP FOR OUR LIFESTYLE NEWSLETTER "The passenger does not know anything is going on," a pilot said. "The flight attendant saw him texting that he was going to hijack the aircraft and called me and we went lockdown. … No restraint, passenger is compliant because he’s unaware." The aircraft eventually departed for Newark Liberty International Airport the following morning. The FAA confirmed it is launching an investigation into the incident, while airport officials deferred further details to United Airlines and the Las Vegas Metropolitan Police Department, Fox 5 Las Vegas reported. The Las Vegas Metropolitan Police Department confirmed that officials arrested a 25-year-old man on suspicion of making threats or conveying false information concerning acts of terrorism in a statement to People. He was subsequently booked at the Clark County Detention Center, according to the outlet. Fox News Digital reached out to the Las Vegas Metropolitan Police Department for additional details. CLICK HERE FOR MORE LIFESTYLE STORIES The pilot informed Air Traffic Control the aircraft was still "grossly overweight" and needed to burn excess fuel before touching down, the audio recording shows. An overweight landing risks adding stress to the plane's landing gear and structural parts, per SKYbrary Aviation Safety. To avoid potential damage during an unplanned landing, planes will sometimes dump fuel or fly longer to burn it off. Reflecting this, flight paths show the aircraft made two loops to burn fuel before returning to land at LAS, per FlightAware. TEST YOURSELF WITH OUR LATEST LIFESTYLE QUIZ In May, another United Airlines flight bound for Minneapolis, Minnesota, made an emergency landing in Madison, Wisconsin, after a passenger allegedly attempted to storm the cockpit, according to air traffic control audio. The flight, which took off from Chicago's O'Hare International Airport, "landed safely in Madison, Wisconsin to address a security concern with an unruly passenger," United Airlines previously told Fox News Digital. The flight landed in Madison's Dane County Regional Airport roughly 90 minutes after takeoff, according to flight tracking data. CLICK HERE TO DOWNLOAD THE FOX NEWS APP While United did not reveal the specific nature of the security concern, air traffic control audio from Dane County Regional Airport reviewed by WISN revealed that the passenger made "multiple attempts to breach the cockpit." Robert McGreevy of Fox News Digital contributed reporting.