Transcript for One Direction, The Wanted Fight it Out on Twitter
14 oh, yeah. Back, now, at 7:42, with the biggest battle since the jets and the sharks went head-to-head here in new york. The two most popular boy bands on the planet, threatening to take their war of words to the streets. And abc's dan harris is here, playing it cool. Reporter: That's right, lara. I always do that. Who doesn't like a big celebrity feud? Biggie versus tupac, nicki minaj versus mariah carry. This one is slightly less menacing. And by slightly less menacing, i say not menacing at all. Here are the combatants, one direction. Known for running on the beach with complicated hair cuts in the video for "what makes you beautiful." And the wanted, known for riding around on bumper cars in the "lose my mind" video.♪ I'm going to lose my mind ♪ Reporter: These two mega british boy bands are in a beef. It's hard tell right now how serious it really is. Reporter: It started when zayne, from one direction, accused max from the wanted, of being a geek on twitter. Zayn is known as the bad boy of one direction. Reporter: Max wrote back, that's not very nice. From there, the witty repertoire went into the use of emoticons and name-calling. Then, max put down the gauntlet. Daring zayn to throw down his problems in new york city, without security. Never wanting to back down, zayn wrote, see you in new york, big man, ha, you clown. Max went public with this interview with radio station 955. Come an see me in new york. Reporter: Ooh. Now, both bands are blocks away from each other at new york hotels. Their respective fans, staked out. Zayn crossed the line. That was so disrespectful. Reporter: All of this trash-talking conjures images of a jets versus sharks "west side story" showdown. And this could come to a head on DECEMBER 7th, WHEN ONE DIRECTION And the wanted are playing the same gig at madison square garden. No word if the nypd has raised the threat level for the city. I've investigated many difficult stories in my day. But this one got to me. And throw a littler in the mix. Lara, whatever you do, don't do that.
This transcript has been automatically generated and may not be 100% accurate.