A 24-year-old woman, who was travelling in a Southwest flight threatened to kill everybody after she prohibited from smoking.

The woman, identified as Valerie Curbello, was arrested after the flight landed in Sacramento, US, reports the Indian Express.

According to a report in KOIN 6, Curbello was first caught smoking in the plane’s washroom, where she had tried to tamper with the smoke detector.

She was subsequently removed from there, but she grew more and more agitated; and in a video that is now going viral, she can be heard screaming that she will ‘kill everyone’.

The flight took off from Portland, US, and one of the passengers, while speaking to KOIN 6 said that Curbello removed an oxygen mask as she got ‘more uncontrollable’.

One of her friends told the news website that Curbello was taken to a mental health crisis centre merely days before the incident happened. At present, she is being held at Sacramento jail.