A United Airlines flight bound for New Jersey returned to Las Vegas after a flight attendant reportedly spotted a passenger texting about hijacking the aircraft, prompting the crew to secure the cockpit and alert air traffic control.United Flight 1681, travelling from Harry Reid International Airport in Las Vegas to Newark Liberty International Airport, returned safely on Saturday night, October 24, following what the airline described as a “potential security concern”.The Boeing 737 was carrying 150 passengers and six crew members. No injuries were reported, according to reports.According to air traffic control audio cited in reports, a flight attendant noticed a passenger sending a message about hijacking the plane and alerted the captain. The crew then secured the cockpit and decided to return to Las Vegas.“The flight attendant saw him texting that he was going to hijack the aircraft,” the pilot reportedly told air traffic control.The passenger was reportedly unaware that the crew had seen the message. Law enforcement officers met the aircraft after it landed in Las Vegas.The Federal Aviation Administration said the flight returned safely and that it would investigate the incident. The Las Vegas airport referred questions to United Airlines and the Las Vegas Metropolitan Police Department.The incident disrupted travel plans for passengers, who were delayed overnight after the aircraft returned to Las Vegas.United said the flight was delayed because the crew had reached its permitted working-hour limit. A replacement flight departed on Sunday morning, October 25, and reached Newark more than eight hours later than originally scheduled, according to USA Today.The airline did not publicly disclose further details about the passenger or the outcome of the investigation in the reports available.