Federal authorities have indicted a Florida man for allegedly posing as Justin Bieber online, promising young girls backstage passes and free tickets in exchange for sexually explicit images and videos of themselves.

Christopher P. Gunn, 31, who is already in custody for related charges in Alabama, is charged with online sextortation and cyberstalking, according to a release by U.S. Attorney of the Northern District of Florida.

In April, the U.S. Sate Attorney of the Middle District of Alabama charged Gunn with two counts of production of child pornography, three counts of interstate extortion, and three counts of possession of child pornography.

Between October 2009 and March 2011, Gunn allegedly preyed upon girls ages 9 to 16 throughout the U.S. and internationally.

Officials were tipped off when students at Pratt Junior High School in Alabama complained that someone using the alias "Tyler Mileke" was asking them for inappropriate pictures on Facebook, according to Clark Morris of the U.S. Attorney's Office.

Authorities traced "Mileke's" IP address back to Gunn's residence and seized his computer. Upon review, investigators found that Gunn used two methods to blackmail girls online and solicit child pornography.

In one, referred to as the "The Justin Bieber Ruse," Gunn reportedly pretended to be the pop singer, using screenames like Justin Babin, justinqazabc123, and surprise.suprise1. Once his victims were convinced he was indeed Bieber, he would promise them fan-related benefits like tickets and passes if they would send him videos or photos of themselves topless, according to the report.

In his other scheme, which officials are calling "The New Kid Ruse," Gunn would reportedly pose as a young boy new in town looking for friends. He'd befriend girls online, gain their trust, and then ask for personal information like bra size and sexual history, officials report.

Officials report that he would then ask for a topless photo: if the girls refused, he would threaten to send their intimate chat to their school principal or post it on Facebook.

For those who supplied him with a topless photo, he would allegedly ask for fully naked shots or even videos of them performing particular sexual acts. If they refused, he reportedly threatened to publish their original topless photos on the Internet.

Gunn's trial is scheduled for September 10. If convicted on all charges in the Florida indictment, Gunn faces over 50 years in federal prison.

Need a palate cleanser? Check out the real Justin Bieber:

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  • NEW YORK - SEPTEMBER 01: Musician Justin Bieber visits the Nintendo World Store on September 1, 2009 in New York City. (Photo by Bryan Bedder/Getty Images)

  • NEW YORK - NOVEMBER 15: Justin Bieber performs on ABC's Good Morning America' at ABC News' Good Morning America Times Square Studio on November 15, 2009 in New York City. (Photo by Michael N. Todaro/WireImage)

  • NEW YORK - DECEMBER 11: Justin Bieber attends the Z100s Jingle Ball 2009 presented by H&M at Madison Square Garden on December 11, 2009 in New York City. (Photo by Jim Spellman/WireImage for Clear Channel Radio)

  • LOS ANGELES, CA - FEBRUARY 13: Singer Justin Bieber poses after his free performance presented by KIIS-FM at Nokia Plaza L.A. Live on February 13, 2010 in Los Angeles, California. (Photo by Angela Weiss/Getty Images)

  • NEW YORK - NOVEMBER 26: Justin Bieber promotes his new book 'First Step 2 Forever' at Barnes & Noble, 5th Avenue on November 26, 2010 in New York City. (Photo by Andy Kropa/Getty Images)

  • LOS ANGELES, CA - MAY 15: Justin Bieber attends KIIS FM's 2010 Wango Tango Concert at Staples Center on May 15, 2010 in Los Angeles, California. (Photo by Jason LaVeris/FilmMagic)

  • Teen idol Justin Bieber arrives on the red carpet for the 68th annual Golden Globe awards at the Beverly Hilton Hotel in Beverly Hills, California, on January 16, 2011. AFP PHOTO/Valerie MACON (Photo credit should read VALERIE MACON/AFP/Getty Images)

  • LONDON, ENGLAND - FEBRUARY 16: Justin Bieber attends the 'Justin Bieber: Never Say Never' premiere at the O2 Cineworld on February 16, 2011 in London, England. (Photo by Jon Furniss/WireImage)

  • LAS VEGAS, NV - MAY 22: Singer Justin Bieber poses in the press room with the Digital Artist of the Year award during the 2011 Billboard Music Awards at the MGM Grand Garden Arena May 22, 2011 in Las Vegas, Nevada. (Photo by Isaac Brekken/Getty Images)

  • NASHVILLE, TN - JUNE 08: Justin Bieber attends the 2011 CMT Music Awards at the Bridgestone Arena on June 8, 2011 in Nashville, Tennessee. (Photo by Jeff Kravitz/FilmMagic)

  • Singer Justin Bieber attends the 2011 BET Awards at The Shrine Auditorium on June 26, 2011 in Los Angeles, California. (FilmMagic)

  • UNIVERSAL CITY, CA - AUGUST 07: Singer Justin Bieber arrives at the 2011 Teen Choice Awards held at Gibson Amphitheatre on August 7, 2011 in Universal City, California. (Photo by Jon Kopaloff/FilmMagic)

  • Singer Justin Bieber arrives at the The 28th Annual MTV Video Music Awards at Nokia Theatre L.A. LIVE on August 28, 2011 in Los Angeles, California. (WireImage)

  • NEW YORK, NY - SEPTEMBER 08: Justin Bieber attends the Dolce & Gabbana Boutique on September 8, 2011 in New York City. (Photo by Eugene Gologursky/Getty Images for Dolce & Gabbana)

  • Singer Justin Bieber poses in the press room at The 53rd Annual GRAMMY Awards held at Staples Center on February 13, 2011 in Los Angeles, California. (Photo by Michael Tran/FilmMagic)

  • ATLANTA, GA - SEPTEMBER 17: (EXCLUSIVE COVERAGE) Musician and 2011 Horizon Award Recipien Justin Bieber poses backstage at the 33rd Annual Georgia Music Hall Of Fame Awards at the Cobb Energy Performing Arts Center on September 17, 2011 in Atlanta, Georgia. (Photo by Ben Rose/WireImage)

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