WATCH: MSNBC host grills Trump-linked radio host interviewed by Mueller's grand jury as he refuses to answer questions

MSNBC's Ari Melber had a testy exchange with Roger Stone associate Randy Credico on the heels of his interview by special counsel Robert Mueller's grand jury as the activist refused to answer any questions.

The stonewalling began when Melber asked Credico which prosecutor investigated him.

"His name starts with an 'A,'" the Stone associate responded.

"Is that as far as you're willing to go?" the host asked, eliciting a laugh from Credico.

Soon, however, the perennial presidential candidate appeared to no longer be amused when the host began asking him about the content of his testimony.

"Were there questions about people trying to shape your testimony in advance or threaten you?" Melber asked.

"You know, you should have been one of the prosecutors there," Credico responded. "No, I'm not gonna tell you that. I really can't tell you that."

The host noted that the Stone associate was legally able to respond, but he continued to refuse, claiming he doesn't want to use his grand jury interview to attain publicity.

Melber asked Credico if he was asked questions about events that took place after 2016 and the radio DJ said there were — but then claimed he's "not supposed to" talk about that per the advice of his lawyers.

"You're circumventing what I can talk about right now, trying to elicit answers," the Stone associate said. 

"I am trying to elicit answers," the host said, "but you know, that's part of my job."

Watch below, via MSNBC: