A drunk woman in her 20s stunned passengers on a plane after slipping off to the toilet to have sex with a man she had just met.

Cabin crew had to intervene after the woman, said to be flying with her parents, disappeared into the toilets with a man sitting next to her.

Witnesses said things had got heated between the woman and the man who was sitting next to her parents en route to Vegas.

Later the frisky couple were caught red-handed when their cries of passion were heard coming from behind the toilet door.

It left cabin crew with no option but to step in but when the newly acquainted lovers were challenged over their behaviour, witnesses say the woman became abusive.

The woman was questioned by police but released with a warning before continuing her holiday in the notorious Nevada resort.

It comes just week after an Australian was arrested for apparently mistaking the cockpit door of a Virgin Australia flight from Brisbane to Bali for the toilet, triggering a hijack scare.

The man told Bali police that he banged on what he thought was the toilet door of Boeing 737-800 aircraft, sparking the terrorism fears.

Last year, Virgin America launched a new service that allows passengers to send drinks, a meal or treats to fellow passengers in a move which many said encouraged mid-air flirting.

Virgin Atlantic said last night they do no accept bad behaviour by any passengers on board their planes.