The Justice Department announced on Tuesday that it was launching a federal civil rights investigation into the death of Freddie Gray, who died after suffering a severe spinal cord injury while in the custody of the Baltimore police.

According to police, the 25-year-old black man was arrested on the morning of Sunday, April 12 after he made eye contact with officers who were patrolling the neighborhood on bike. Once Gray fled the scene, police pursued him and took him into custody for carrying a switchblade knife. However, in a cellphone video captured by witnesses, Gray's legs appear to be limp as he is dragged into a police van.

A report also notes that "the defendant was arrested without force or incident," while none of the six officers involved in the arrest describe using force against him, reports The New York Times.

Although Gray was able to talk and breathe when he was placed inside of the van, he was unresponsive by the time officers sought to remove him.

"And when Mr. Gray was taken out of that van, he could not talk, and he could not breathe," according to Deputy Police Commissioner Jerry Rodriguez.

Police say Gray requested medical attention, including an asthma pump, before he was taken to the University of Maryland Medical Center's Shock Trauma Center, where he died exactly one week later.

As of now, officials say it is not clear who or what caused the spinal cord injury that led to his death. It is also unknown if something happened to him while inside the van.

Following his death, demonstrators held a series of protests demanding answers and justice for Gray. In the meantime, six police officers have been suspended and officials said Monday that they were changing police procedures.

City officials held a news conference on Monday pleading for city residents to keep calm in wake of the investigation to figure out exactly how Gray was injured.

"We have no evidence -- physical, video or statements -- of any use of force," said Commissioner Rodriguez at the conference, reports the NYT. "He did suffer a very tragic injury to his spinal cord, which resulted in his death. What we don't know, and what we need to get to, is how that injury occurred."

Rodriguez added that the results of from an investigation would be handed to prosecutors by May 1. Prosecutors will then decide if any criminal charges will be pressed in the case.

On Tuesday afternoon, Justice Department spokesperson Dena Iverson announced that, "based on preliminary information," it was opening a probe to see if any civil rights violations occurred, reports the Washington Post.

Watch video of Freddie Gray being arrested below.