In light of a recent book that claims the killers of Malcolm X never paid for their crime, the U.S. Department of Justice is considering reexamining the case.

The department is reviewing "the request to open the Malcolm X murder," department spokesman Xochitl Hinojosa said Monday. "We decline further comment at this time."

Alvin Sykes, architect of the Emmett Till Unsolved Civil Rights Crime Act, asked Attorney General Eric Holder to open a new investigation into the murder.

He told The Clarion Ledger's Jerry Mitchell that he would like to see the Justice Department use "more investigative resources and prosecutorial jurisdiction to credibly address the guilt or innocence of a broader net of past, present and potentially future suspects in this case."

"Malcolm X: A Life of Reinvention," the new biography by Columbia University professor Manning Marable, explains why the investigation should be reopened. Marable died earlier this month, just days before publication of the book.

"Professor Marable believed in justice," Zaheer Ali, Marable's chief researcher, told CBS News. "And his killers were never served justice."

Malcolm X was killed on Feb. 21, 1965 while speaking at the Audubon Ballroom in upper Manhattan when three men opened fire. Talmadge Hayer was arrested on the scene and confessed to the shooting during trial. He also testified that Norman 3X Butler and Thomas 15X Johnson -- the two other men charged with the shooting -- were not present during the crime.

All three men were convicted and have since been paroled.

"As Marable's quite powerful book details, four of the actual assassins never were pursued and at least one of them still lives openly in the metro New York area," historian and author David Garrow said recently.