Major airline 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.

CLICK HERE TO SIGN UP FOR OUR LIFESTYLE NEWSLETTER

The aircraft eventually departed for Newark Liberty International 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.

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.

CLICK HERE FOR MORE LIFESTYLE STORIES

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.

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.