"I know for a fact that he (Gray) did not hurt himself," Donta Allen, who was a fellow prisoner in the van during a portion of the meandering path of the vehicle after Gray was taken into the custody and before medical help was summoned, told CNN's Don Lemon in an interview. Reciting a litany of Gray's injuries, Allen added "you cannot do that (to yourself) in the paddy wagon. You can probably hit your head and have a little headache, but you can't hurt yourself to the point you're going to be dead."
And as for a report in the Washington Post that he told investigators he had heard noises indicating Gray was trying to injure himself, "untrue. Very, very, very untrue," said Allen.
During the interview, airing Friday on "CNN Tonight," Allen said at the police station, as he was being taken to the "bullpen" area for incoming prisoners, he overheard a female police officer say, "Well, you know, we gave him a run for his money -- he's not breathing."
"I don't know who, but I heard police saying that," Allen told Lemon. "They weren't saying it like, 'Guys, we really have a problem here.'"
As he was waiting in the bullpen, Allen said, "An officer lady came in and she's like, 'Well, he's got vitals now.'"
Police have not discussed specifics of what took place at the police station.
On Friday, six police officers were charged in Gray's death.
Michael Davey, an attorney for the Baltimore Fraternal Order of Police who spoke on behalf of the six officers and their attorneys, told reporters Friday that none of the officers injured or harmed Gray.
"They are truly saddened by his death," Davey said. "These officers did nothing wrong."
Gray died on April 19 after suffering a spinal injury while in police custody a week before. His death sparked protests against police in Baltimore, which later spread to major cities nationwide. Court documents said Gray was arrested after running away from the police.
Allen said that during the time he was in the van, which was near the end of the course taken by the van after Gray was picked up, he had no idea who was on the other side of the partition. He said he had known Gray from the neighborhood, but only by his first name.
"I never see who's in the van," Allen said. "They (police) never tell me somebody else is in the van."
The only sound he heard from the other side, Allen remembered, was "a little banging, like someone was over there banging their head or something."
His portion of the ride was smooth, Allen said. "No stops, we went straight to the police station."
Allen said he was in custody after being accosted by officers as he was leaving a store empty-handed. He said he was searched, officers found a small amount of marijuana on him, and called for the police transport van.
At the police station, he was questioned by a homicide investigator with general questions about crimes that had happened in the area, then he was released without explanation, Allen said.
"They never booked me, never charged me."
Asked by Lemon if he was afraid now, Allen said, "I'm telling the truth and I know they don't want me to tell the truth.
"I know they're gonna try to harass me after this. But I'd rather for them to harass me than my own people to harass me for a lie they made up."