Joran Van der Sloot arrives for a hearing at the Lurigancho prison in Lima, Peru, on January 11, 2011.
CNN  — 

Joran van der Sloot, the suspect in the unsolved 2005 disappearance of Alabama teenager Natalee Holloway who is accused of extorting and defrauding the teen’s mother, is expected to enter a guilty plea to federal charges at a Wednesday hearing, an attorney for her family says.

It is not known what specific charges in the extortion case he will plead guilty to, or what the sentence will be.

Van der Sloot, one of the last people seen with the 18-year-old Holloway before she vanished, was indicted in 2010 on federal charges of extortion and wire fraud in connection with a plot to sell information about the whereabouts of Holloway’s remains in exchange for $250,000, according to an indictment filed in the Northern District of Alabama.

Holloway family attorney John Q. Kelly confirmed to CNN van der Sloot intends to plead guilty in connection to the case.

Kelly told NBC’s “Today” show that a condition of the plea deal requires Van der Sloot to reveal details of how Holloway died and how her body was disposed of.

“There won’t be any further investigation or search … for Natalee’s remains,” Kelly said on “Today.”

Beth Holloway, Natalee’s mother, will hold a news conference following the hearing to make public what van der Sloot told FBI authorities.

CNN has sought further information from Kelly and has also sought comment from the US Justice Department and police in Aruba, where Holloway disappeared.

Van der Sloot was transferred in June to the United States from a prison in Peru, where he was serving a 28-year sentence for the 2010 murder of Stephany Flores, 21, in his Lima, Peru, hotel room.

Under the agreement between Peru and the US, van der Sloot would first return to Peru to finish the murder sentence in the Flores case, and then would be brought back to the US to begin serving whatever sentence he receives for US-based charges.

According to the indictment, Holloway’s mother wired $15,000 to a bank account van der Sloot held in the Netherlands and through an attorney gave him another $10,000 in person. Once he had the initial $25,000, van der Sloot showed the attorney, Kelly, where Natalee Holloway’s remains allegedly were hidden but later admitted by email the information was “worthless,” the indictment states.

The teenager was last seen 18 years ago leaving a nightclub with van der Sloot and two other men on the Dutch Caribbean island of Aruba. Police in Aruba arrested and released van der Sloot and brothers Deepak and Satish Kalpoe multiple times in 2005 and 2007 in connection with Holloway’s disappearance. Attorneys for the men maintained their innocence throughout the investigation.

In December 2007, the Aruban Public Prosecutor’s Office said none of the three would be charged and dropped the cases against them, citing insufficient evidence.

A judge in Alabama signed an order declaring Holloway legally dead five years later.

Correction: A previous version of this story incorrectly stated the year Stephany Flores was killed. Flores died in 2010.

CNN’s Tina Burnside contributed to this report.