The Welsh Rugby Union (WRU) has launched an investigation after complaints from passengers about the conduct of members of Pontypridd's Rhydyfelin RFC on board an Easyjet flight last month.
Police removed a man from the Easyjet flight from Bristol Airport to Majorca
Passenger Mike Dudley, president of Cross Keys RFC, told Wales Online of the boys: "They were boasting they had been drinking for hours before getting on the plane.
"I was amazed they were allowed on it by security staff at Bristol Airport because of the state some were clearly in.
"As a consequence of their misbehaviour, foul, abusive and threatening language, English subjects and other nationals on the flight must now have an extremely low opinion of people from Wales.
"I urge the Welsh Rugby Union (WRU) to take firm action against Rhydyfelin RFC and ban the club from touring because what happened was utterly disconcerting and dangerous."
Another passenger, Karen Jones, said: "The party appeared to be inebriated when they boarded the plane using very loud unacceptable expletives and were disrespectful to the female cabin crew members.
She added the behaviour "had a direct impact on other travellers who were offended by it and also fearful for their safety."
A spokesman for Rhydyfelin RFC has insisted that the man removed from the plane was not an RFC member, although he was wearing a club shirt.
The boys were reportedly heading off on a stag weekend.
An EasyJet spokesman told the South Wales Evening Post: "Flight EZY6039 from Bristol to Palma on April 26 was met by police in Bristol due to a passenger on board behaving in a disruptive manner.
"The safety and wellbeing of passengers and crew is always EasyJet's priority.
"Whilst such incidents are rare we take them very seriously, do not tolerate abusive or threatening behaviour on board, and always push for prosecution."
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