June 6 (UPI) -- The Dutch man suspected in the 2005 disappearance of Natalee Holloway is challenging his extradition to the United States on fraud charges, his lawyer said.
Attorney Máximo Altez told NBC News he plans to file a writ of habeas corpus for Joran van der Sloot, who is set to be extradited to Alabama on Thursday charges of a fraud scheme connected to Holloway.
"I don't know how they'll extradite him," Altez said. "He's not willing to do it voluntarily."
Holloway vanished at age 18 on the Dutch Caribbean Island of Aruba while on a high school graduation trip May 30, 2005. She was last seen leaving an Oranjestad nightclub, with three young men, including van der Sloot.
Van der Sloot was arrested in Holloway's disappearance but never charged. He is serving a 28-year sentence in Peru for killing a 21-year-old Peruvian woman in 2010.
As part of an alleged fraud scheme, Van der Sloot is accused of trying to extort hundreds of thousands of dollars from Holloway's family in exchange for the details of her death.
Prosecutors say he lied to the family about where her remains were located.
Last month, the Peruvian government agreed to temporarily release Van der Sloot to the United States.