Malcolm X
CNN

Almost 50 years ago, Malcolm X, who had risen to prominence as one of the most outspoken and public faces of the Nation of Islam, was gunned down inside the Audubon Ballroom in New York City. And ever since his death Feb. 21, 1965, there has been speculation as to who had the civil rights leader murdered.

Some have argued that the government was complicit in his death; others have argued that his public feud with NOI leader Elijah Muhammad may have led to his assassination. On Tuesday at 9 p.m., CNN premieres Witnessed: The Assassination of Malcolm X, a special report that asks some of those who were there when the shooting occurred—photographer and friend Earl Grant, former radio reporter Gene Simpson, Malcolm X's daughter Ilyasah Shabazz and Peter Bailey, an associate of Malcolm's—to share their memories.

"We failed him; I tried to help him," Grant cries as he talks about the horrifying, chaotic situation inside the Audubon Ballroom. Grant takes viewers inside his private photo collection, sharing never-before-seen images of the civil rights icon.

Zaheer Ali, who was project manager of the Malcolm X Project at Columbia University, leads an online experience at cnn.com that delves into the unanswered questions surrounding the assassination. Bailey describes Malcolm's plan to expose injustices against black Americans before he was gunned down, and Simpson, who was in the front row of the Audubon Ballroom when Malcolm took the stage, discusses the first time he interviewed the civil rights leader.