But Mr. Stone has insisted that he had no prior knowledge and that he was acting off what the WikiLeaks founder, Julian Assange, had said publicly that summer, as well as information from his longtime associate Randy Credico, who had contacts close to Mr. Assange.

“Did I want to know what WikiLeaks had? Of course I did,” Mr. Stone said on Monday, adding, “I still never had any advance knowledge of the content, or the form, or the exact timing” of when the emails would be leaked.

“I never got any material including allegedly hacked emails from WikiLeaks or Assange and passed them on to Donald Trump,” Mr. Stone said. “I never got anything from the Russians, whoever that is.”

Mr. Caputo was among those who was questioned about Mr. Stone’s connection to the campaign, as well as text messages he and Mr. Stone exchanged, according to two people briefed on the questions.

Mr. Stone said he never had any relationship with Mr. Assange. And he said that his lawyer had written to House Intelligence Committee officials asking for a correction to testimony he gave in the panel’s own investigation into Russia’s election interference.

The testimony addressed one of Mr. Stone’s tweets about the hacked emails, which were stolen from the account of Hillary Clinton’s campaign chairman, John Podesta. Two months before the emails were released, Mr. Stone predicted on his since-suspended Twitter account that it would soon be “Podesta’s time in the barrel.”

The tweet, his lawyer said, contained a grammatical error — the apostrophe. Mr. Stone had meant that to write that it would soon be “the Podestas’ time in the barrel” and was attempting to refer to Mr. Podesta and his brother, Tony, a major lobbyist, his lawyer said.