Lance Bass (left) and 50 Cent Photo by: Jim Spellman / WireImage; New York Daily News / WENN
Latest Celebrity Feud: Lance Bass vs. 50 Cent | 50 Cent, Lance Bass
Forget the East Coast-West Coast rap rivalries of the past. The latest celebrity feud has a former boybander and a top rap star dishing out threats.

Lance Bass and 50 Cent (real name: Curtis James Jackson III) are releasing books at the same time, and even held their launch parties on the same night. At 50's party in New York's Philippe Tuesday, he told the New York Daily News that Bass better watch his back. "He doesn't stand a chance," the rapper said as he promoted his coffee-table book, 50 x 50.

Later that night, at Bass's own NYC launch party at hotspot Azza for his new tell-all book, Out of Sync: A Memoir, the former 'N Sync member – who came out in 2006 to PEOPLE – hit back at the rapper.

"50's going down, that's all I have to say," he joked. "50, I don't want to playa-hate, but there's a lot that my book has [that yours doesn't].

Including, Bass says, two things in particular: "I'm pretty sure he doesn't have any relationships with guys in that book. And I'm pretty sure he doesn't have any space training, either."

50 added, he's been in this situation before. "With me, everything's a competition, so I bet you the end of next week, I'll be moving more copies than him," 50 said. "This is the same competition – this is Kanye West and 50 Cent all over again!"


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