The man who used his cellphone to record video of Freddie Gray's arrest by Baltimore police officers was himself arrested by officers after he left a protest on Thursday, in what he describes as a clear case of witness intimidation.

Baltimore police arrested Kevin Moore along with two friends of his from Ferguson, Missouri, who work with the group Copwatch, an activist organization that advocates for the filming of interactions with police. Police released Moore on Friday morning without charges being filed against him. His two companions, Chad Jackson and Tony White, remain in custody.

Moore told VICE News that, prior to his arrest, the police department's internal affairs division had already interviewed him for several hours about what he witnessed when Gray was arrested. His video showed the arresting officers lifting Gray from the ground where they had handcuffed him and carrying him limply to the back of a police van. Gray was later determined to have a severed spine and died a week after his arrest.

The Baltimore State's Attorney's Office announced on Friday that it had filed criminal charges against the six officers involved in Gray's arrest and subsequent death.

Moore described the circumstances of his arrest on Thursday to VICE News on video and in an off-camera interview.

"They waited until I got away from the protest and my people to protect me," he said.

Police arrested Moore, Jackson, and White after the three of them walked to Bruce Court, an area where Moore lives that is located not far from the site of the protest. The pretext for the arrest was not clear.

"They had assault weapons, rifles, they had everything — their tank, two choppers," he recalled. "They took me to the Western District [police station], never gave me charging papers or anything."

"It's called witness intimidation," he added. "But if they hadn't let me go it would have been a whole lot of BS that they didn't want to deal with, so they decided it was in their best interest to let me go. But they still have my friends."

Chuck Modiano, a member of Copwatch, told VICE News that jail support informed the group that Jackson and White will probably be released sometime in the afternoon on Friday. To his knowledge, no formal charges are being filed. Modiano said that Copwatch did not know on what grounds police were holding the two activists.

The Baltimore Police Department did not answer inquiries from VICE News about their arrests.

"I have a feeling there's some foul play going on," Moore said, noting that the police did not give him even a citation.

Moore said he felt intimidated by the police when they earlier sought to question him about Gray's death, and particularly after they subsequently circulated his photo and personal information online, saying that he was wanted for questioning.

"They plastered my picture all over the internet hoping people would come forward and tell on me," Moore said. "I gave them that video... They asked me, like, 'You seem like you are a positive leader in your community.' And [I was like], 'Oh, so you know who I am?' I'm not hiding, I've never been hiding."

Moore praised the decision this morning by Baltimore State's Attorney Marilyn J. Mosby to press criminal charges on the officers involved in Gray's death, and said that he is determined to seek "justice for my man Freddie."