Justin Bieber tweeted one of his enemies' phone numbers on Saturday night, tricking some of his 4.5 million followers into believing the number was his own. The phone number actually belonged to a Detroit teenager named Kevin Kristopik, who Bieber doesn't know but who has been annoying the pop star with unwanted text messages. Bieber's tweet was promptly deleted from his page, but not before his followers saw the number and flooded it with an estimated 26,000 texts and countless phone calls. Kristopik's father is worried about the massive phone bill he'll be receiving, and says Bieber was "out of line." Well, it "looks like the Biebs may not be so innocent after all," says the Wall Street Journal. Actually, it raises the question of whether Bieber might face criminal charges or a civil lawsuit, says Leslie Gorenstein at E! Online. "Not likely, attorneys tell me." See a video of Kristopik's cell phone blowing up after Bieber's "evil" prank: