Washington (CNN) Michael Cohen, the one-time personal attorney and fixer to President Donald Trump, on Wednesday presented an extensive set of his former boss's possible criminal liabilities that Cohen described as under investigation by federal prosecutors in New York.

In public testimony before Congress, Cohen provided fresh details about Trump's participation in Cohen's campaign finance crimes, including steps that occurred after Trump took office, and revealed that prosecutors are investigating other unspecified criminal activity by Trump.

Cohen also told the House Oversight Committee that Trump Organization executives, including the President's son Donald Trump Jr. and Chief Financial Officer Allen Weisselberg, participated in what prosecutors have described in court documents as a scheme to reimburse Cohen for a $130,000 payment he made to silence an adult-film actress, Stormy Daniels, who claimed an affair with Trump.

And Cohen testified that Trump had an arrangement stretching back more than a decade with David Pecker, the CEO of American Media Inc., which publishes the National Enquirer tabloid, to eliminate stories that could prove detrimental to Trump if published.

In an effort to corroborate his claims, particularly those concerning an alleged reimbursement payment by Trump himself, Cohen came armed with copies of checks. One, dated August 2017, seven months after Trump was sworn into office, came from Trump's personal bank account and appeared to showed Trump's distinctive signature authorizing what Cohen testified was partial reimbursement by the sitting President.

Cohen's testimony dramatically expanded the scope of what is publicly known about New York federal prosecutors' examination of the President, his company and his family.

Prior to Wednesday, prosecutors in the Southern District of New York were known to have been examining whether any Trump Org executives violated campaign-finance laws as part of the scheme to reimburse Cohen and had been conducting an investigation of the Trump inaugural committee, CNN has reported.

On Wednesday, Cohen suggested they are also examining a conversation he had with Trump in the spring of 2018, within two months of the FBI having executed search warrants on Cohen's home, hotel room and office.

After telling the committee that conversation was the last time Cohen spoke to Trump, Cohen said he couldn't speak further about that matter because it is under investigation by prosecutors. "I've been asked by them not to discuss and not to talk about these issues," Cohen said.

Minutes later, Cohen was asked: "Is there any other wrongdoing or illegal acts that you are aware of regarding Donald Trump that we haven't yet discussed today?" Cohen replied: "Yes, and again those are part of the investigation that's currently being looked at by the Southern District of New York."

At another point, Cohen disclosed: "I am in constant contact with the Southern District of New York regarding ongoing investigations."

A spokesman for the US Attorney's Office declined to comment on Cohen's testimony.

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Stormy Daniels payment another legal problem for Trump

The newly disclosed investigative efforts aren't the only aspect of Cohen's testimony that may spell significant legal trouble for Trump. For the first time, Cohen publicly described in great detail Trump's participation in and direction of Cohen's payment to Daniels and the effort to reimburse him for that payment.

Cohen told the committee that in 2016, when Cohen was engaged in discussions with Daniels's then-attorney about whether to pay Daniels to remain silent, "what I did each and every time is go straight into Mr. Trump's office and discuss the issue with him."

Days before the election, when a leaked tape of Trump making crude comments about women on the set of "Access Hollywood" created what Cohen described in his testimony as a "wildfire," Cohen said he met with Trump and Weisselberg in Trump's office, and Trump decided to pay Daniels.

"He acknowledged to Allen that he was going to pay the $130,000, and that Allen and I should go back to his office and figure out how to do it," Cohen said.

According to Cohen, he asked Weisselberg to use his own money to pay Daniels. After Weisselberg said he couldn't, Cohen said, Weisselberg suggested to Cohen that the two find someone who "wants to have a party at one of his clubs that could pay me instead, or somebody who may have wanted to become a member of one of the golf clubs."

After concluding that they didn't know anyone who could cover for them in such a manner, Cohen said he decided to use his home-equity line of credit to make the Daniels payment. Trump knew of and approved that step, as well as the entire reimbursement scheme, Cohen said.

"Oh, he knew about everything, yes," Cohen told the committee.

Federal prosecutors have previously explained the scheme in court filings, saying that Cohen falsely submitted invoices to the Trump Organization at the direction of "executives" of the company during the year 2017, for a total of $420,000. The reimbursement was paid in monthly installments of $35,000, according to prosecutors.

In court filings, prosecutors cited two company executives ("Executive-1" and "Executive-2") who were involved in the reimbursement scheme, but didn't name them. On Wednesday, Cohen testified that he "believed" that Weisselberg, who had limited immunity and provided information to investigators, is "Executive-1" and that Trump Jr. is "Executive-2."

Cohen also made public a copy of what he said was one of the $35,000 reimbursement checks, signed by Weisselberg and Trump Jr.

"Are you telling us, Mr. Cohen, that the President directed transactions in conspiracy with Allen Weisselberg and his son, Donald Trump Jr., as part of ... a criminal conspiracy of financial fraud? Is that your testimony today?" Rep. Ro Khanna asked.

"Yes," Cohen replied.

An attorney for Trump Jr. declined to comment on Cohen's claims.

"Is there any doubt that President Trump knew exactly what he was paying for?" Cohen was asked at another point in the hearing. "There is no doubt in my mind," Cohen said.

Though federal prosecutors didn't reference a check from Trump in their charges against Cohen, they obtained evidence of such a from Trump's personal account during their investigation, according to a person familiar with the matter.

Catch-and-kill

Cohen also resurfaced details of Trump's efforts to suppress unflattering stories with the help of Pecker, who received immunity from prosecutors.

Cohen testified that Pecker had helped kill a prospective story on an alleged Trump love child. A tip about that story was obtained by AMI, but the story was never published by the National Enquirer after AMI paid $30,000 in August 2015 to a former doorman at Trump World Tower, Dino Sajudin, who was selling the rights to what he claimed was information that Trump had fathered a child with a former employee. No outlets, including CNN, have found any evidence to support the allegation about the child.

The $30,000 contract, however, was scrutinized by federal prosecutors in New York in the spring of 2018 as a third hush money payment, according to people familiar with the matter.

Cohen had told media outlets that his involvement in the matter was limited to trying as Trump's spokesman to tamp down what AMI said were its efforts to confirm Sajudin's tip. But in fact, Cohen was involved much earlier in the process than previously known, people familiar with the matter said, and helped engineer the contract between AMI and Sajudin in the same manner he later orchestrated another hush money contract to an ex-Playboy model, Karen McDougal, according to two people involved in the process.

Investigators ultimately decided against charging it as a crime. It's not clear why prosecutors didn't pursue charges over the Sajudin contract, but former officials from the Southern District of New York suggested that prosecutors may have considered the timing of the contract to be too far removed from Election Day to make as compelling of a case as the payments to McDougal and Daniels.