Justin Bieber Yelling Curse Words on a Plane?

Justin Bieber fielded an unusual request from a passenger on an international flight. It all happened during Justin’s return from his promotional tour in New Zealand last weekend.

From TMZ:

Justin Bieber was surrounded by his entourage in first class when things started getting out of hand.

We’re told Justin and his posse were blurting out cuss words — including some 4-letter selections — and getting so loud … a female passenger finally stepped to Bieber.

We’re told the woman … a mother of 2 … walked over and asked Justin to “stop yelling curse words and using that kind of language on a plane. It’s not appropriate.”

A source close to Justin tells us he was completely embarrassed, quickly apologized to the woman.