Story by the Associated Press; curated by Dave Urbanski and Zach Noble

FERGUSON, Mo. (AP) — U.S. Attorney General Eric Holder on Sunday ordered a federal medical examiner to perform another autopsy on the body of a black Missouri teenager whose fatal shooting by a white police officer has spurred a week of rancorous and sometimes violent protests in suburban St. Louis.

Image source: AP/Pablo Martinez Monsivais, File

Image source: AP/Pablo Martinez Monsivais, File

Department of Justice spokesman Brian Fallon cited a request by family members and the “extraordinary circumstances” surrounding the case of 18-year-old Michael Brown in explaining decision.

“This independent examination will take place as soon as possible,” Fallon said in a statement. “Even after it is complete, Justice Department officials still plan to take the state-performed autopsy into account in the course of their investigation.”

The Justice Department already had deepened its civil rights investigation of the shooting. Officials said a day earlier that 40 FBI agents were going door-to-door gathering information in the Ferguson, Missouri, neighborhood where an unarmed Brown was shot to death in the middle of the street on Aug. 9.

David Weinstein, a former federal prosecutor who supervised the criminal civil rights section of Miami’s U.S. Attorney’s office, said a federally conducted autopsy “more closely focused on entry point of projectiles, defensive wounds and bruises” might help that investigation, and that the move is “not that unusual.”

He also said federal authorities want to calm any public fears that no action will be taken on the case.

In addition to the federal and state autopsies, Brown’s family has requested a third autopsy, CNN reported.

It will be conducted by high-profile pathologist Michael Baden, according to Anthony Gray, a lawyer for the Brown family, CNN noted.

Baden testified in the O.J. Simpson, Phil Spector and Drew Peterson murder trials, CNN added.

This story has been updated.

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