Justin Bieber and his father were  ?extremely abusive? to a flight attendant as their private jet flew from  Canada to New Jersey on Friday, forcing her to take refuge in the  cockpit, according to an official report obtained exclusively by NBC  News.
According to multiple law  enforcement sources, the leased, luxurious Gulfstream IV on which the  19-year-old Canadian pop star, his father and an entourage of 10 friends  traveled was so full of marijuana smoke that the pilots were forced to  wear oxygen masks.
                      
 The captain of the  flight stated that he warned the passengers, including Bieber, on  several occasions to stop smoking marijuana, says the official report  of the incident. The captain also stated he needed to request that the  passengers stop their harassing behavior toward the flight attendant and  after several warnings asked the flight attendant to stay with him near  the cockpit to avoid any further abuse.
According  to multiple sources, the attendant was forced to spend much of the  flight near the pilots as the plane travelled from Canada to Teterboro,  N.J.
The flight attendant stated  the passengers, including Bieber and his father, Jeremy Bieber, stated  the report, were extremely abusive verbally and she would not work  another flight with them.
The  pilots, despite a pressurized cabin, were forced to wear their oxygen  masks during the flight, according to multiple sources, so that they  wouldnt risk inhaling marijuana and failing any subsequent drug test,  which would put their licenses at risk.