A United Airlines flight bound for New Jersey returned to Las Vegas shortly after take-off on Saturday, after a flight attendant reportedly saw a passenger texting that he planned to hijack the aircraft.

United Flight 1681, carrying 150 passengers and six crew members, was travelling from Harry Reid International Airport in Las Vegas to Newark Liberty International Airport when the crew reported a potential security concern.

According to CBS News , the flight attendant alerted the pilot after noticing messages referring to taking control of the aircraft. The crew did not confront the passenger, and the pilot informed air traffic control that the plane was returning to Las Vegas.

Pilot tells air traffic control about alleged threat

In audio recordings of communications with air traffic control, the pilot said the flight attendant had seen the passenger “texting that he was going to hijack the aircraft”.

The pilot told the controller that the crew had gone into lockdown, adding that the passenger was…