FILE - In this Nov. 22, 2017, file photo, Dr. Larry Nassar, appears in court for a plea hearing in Lansing, Mich. Nassar, an elite Michigan sports doctor who possessed child pornography and assaulted gymnasts, was sentenced Thursday, Dec. 7, 2017, to 60 years in federal prison in one of three criminal cases that ensure he will never be free again. (AP Photo/Paul Sancya, File)

▶ Watch Video: Watchdog report finds FBI botched sexual abuse investigation into Larry Nassar

Washington — The FBI has fired an agent who failed to investigate allegations against former USA Gymnastics doctor Larry Nassar ahead of a congressional hearing centered on the agency’s improper handling of the child sex-abuse investigation, sources familiar with the matter tell CBS News.

FBI Director Christopher Wray, who rose to the position after the FBI’s botched Nassar investigation, is slated to appear before the Senate Judiciary Committee on Wednesday to testify about the bureau’s failure to pursue allegations against the former doctor, who has been sentenced to over 100 years in prison for sexual abuse and child pornography crimes.

The Washington Post first reported the agent’s firing.

Wray plans to deliver a scathing statement at Wednesday’s hearing, which will address his outrage over what happened in the Nassar investigation, sources briefed on his remarks tell CBS News.

Wednesday’s hearing will feature four current or former gymnasts who say Nassar sexually abused them by co-opting their medical treatment during his time as a USA Gymnastics doctor: Simone Biles, McKayla Maroney, Aly Raisman and Maggie Nichols.

A July report by Justice Department Inspector General Michael Horowitz harshly criticized a supervisory special agent in the FBI’s Indianapolis office and Jay Abbott, the agent in charge of the FBI’s Indianapolis field office, for bungling the Nassar case and later lying about it. Abbott retired in 2018.

The report said the FBI’s Indianapolis field office first learned of the accusations in July 2015 after USA Gymnastics conducted its own internal investigation. But the FBI did not open an investigation in Michigan, where the abuse occurred and where Nassar was still working at Michigan State University, until October 2016. The FBI did not take action until USA Gymnastics filed a new complaint in Los Angeles following months of inactivity in Indianapolis, the report said.

Nassar abused additional athletes after the allegations were first brought to the FBI’s attention, the report said. The inspector general also accused the FBI of failing to “formally document” the initial meeting when the allegations were brought to their attention.

Jordan Freiman contributed to this report.

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