From left: Muhammad A. Aziz and Khalil Islam in 1965

Two of the three men convicted of 1965 killing civil rights leader Malcolm X will soon be exonerated, Manhattan's district attorney announced Wednesday.

After a 22-month investigation, District Attorney Cyrus Vance Jr. found that authorities withheld evidence in the trial of Muhammad A. Aziz, 83, and the late Khalil Islam, who died in 2009, the New York Times reported. Both men spent over two decades in prison for a crime they vowed they did not commit.

Vance Jr. will hold a news conference Thursday to announce the investigation's findings.

Malcolm X, who was born Malcolm Little, was killed while giving a speech at New York's Audubon Ballroom on February 21, 1965. Aziz, Islam, and another man, Thomas Hagan, were convicted for the murder, but Aziz and Islam maintained their innocence.

However, Vance's investigation found that key physical evidence and documents were lost over the years, the murder weapons could no longer be tested, and many witnesses, investigators, and potential suspects have since died, the Times reported. FBI documents implicated other suspects and "pointed away" from Islam and Aziz, the report said.

"This points to the truth that law enforcement over history has often failed to live up to its responsibilities," Vance told the publication. "These men did not get the justice that they deserved."

In November 2020, a letter from former undercover NYPD officer Raymond Wood was released. Wood claimed he was coerced by his NYPD supervisors to lure members of Malcolm X's security detail into committing crimes that resulted in the FBI arresting them days before the shooting.

"There was no security to prevent the gunman from coming into the building," his cousin, Reginald Wood Jr. said.

The district attorney's office opened the investigation following the release of the Netflix documentary "Who Killed Malcolm X?" Phil Bertelsen, who produced the documentary, spoke about the film with the "CBS Evening News."

"The FBI had eyewitness testimony from presumably the nine informants that were in the room that day about who did the crime. Full descriptions of the men, and particularly the man who wielded the shotgun. That was information that was not given to the NYPD," Bertelsen said.

In February, Malcolm X's daughter, Ilyasah Shabazz, told CBS News her family always had questions about her father's death. "I can say I was surprised because I was caught off guard, but it's something that my family and many always wondered. But most importantly, we wanted to ensure that the truth is uncovered," she said.