Did Gay Slur Prompt Justin Bieber to Punch Boy?

In just two years, 16-year-old Canadian singing sensation Justin Bieber has become one of the biggest stars of popular music.

But Friday night, "Early Show" co-anchor Erica Hill reports, Bieber was trying to be just a typical teen, playing laser tag at an arena in Vancouver.

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Dylan Howard, of RadarOnline.com, told CBS News Bieber was attending a laser club with some 12 people as part of his entourage.

Then, at some point, the game of tag apparently turned ugly.

According to TMZ.com, the Royal Canadian Mounted Police have determined that an unnamed 12-year-old-boy got into an argument with Bieber and referred to him with a gay slur.

Howard says, "It's alleged that the 12-year-old boy in question taunted Bieber and provoked him into assaulting him."

The boy is said to have cornered Bieber during the game, "shooting" him repeatedly. When Bieber told him to stop -- the boy may have used the gay slur -- and more than once.

The boy claims Bieber punched him.

It's the first time Bieber's world has spun off its carefully orchestrated axis since he broke on the scene in 2008, Hill notes.

His first two albums went platinum. His video, "Baby," topped Lady Gaga's "Bad Romance" for the most-viewed YouTube video ever.

And now Bieber -- who is not gay -- says he plans to join the campaign against bullying and homophobia that has sprung up in the wake of several gay teen suicides in recent weeks.

TMZ says Bieber told friends he had no idea how hurtful such remarks could be, and plans to speak out publicly sometime next week.