Justin Bieber got some good press this weekend when he went on a pre-Valentine's Day date with a six-year-old cancer patient from Massachusetts, but could that all be undone by a crude comment and hand gesture he made to a fan at Disneyland on Valentine's Day.

The young pop star was visiting the theme park with girlfriend Selena Gomez and his family (including at least Jeremy Bieber, his father) when a fan spotted him on a ride about to enter a tunnel. Giggling, she said to him, I follow you on Twitter! (Yeah, her and 17.5 million other people...) He was then filmed giving her the middle finger and saying, F--k you! Check out the video here, which is shakey but has the offending gesture isolated and repeated:

In YouTube comments to the video, true Beliebers sprung into action to defend the star, with one person saying She isn't a Belieber -.- If u see your idol, you don't gonna say 'I follow? you on twitter', and another writing, She deserved it! she was probably a? hater.