American Media, the publisher of the National Enquirer, was subpoenaed by federal prosecutors for records related to a $150,000 payment made to ex-Playboy model Karen McDougal, people familiar with the matter told the Wall Street Journal.
The subpoena is part of a criminal investigation of President Donald Trump's former lawyer, Michael Cohen, the Journal reported Wednesday. Cohen, who has not been charged, is currently involved in court proceedings over the raft of materials seized from his properties in raids by federal agents in April.
American Media made the payment to McDougal in exchange for the rights to her story alleging she had an affair with Trump more than a decade earlier. The publisher never ran the story, in a practice reportedly known within the industry as "catch and kill."
The White House has denied Trump had sex with McDougal.
Lawyers for Cohen did not immediately respond to CNBC's requests for comment. A spokesman for Keith Davidson, who was the ex-model's lawyer at the time of the payment, did not immediately respond to CNBC's request for comment.
The newspaper, citing other people familiar with the matter, reported that investigators are looking into any potential efforts by Cohen to quash damaging information about Trump during his presidential campaign. Those potential efforts could include whether he coordinated with the publisher in the deal with McDougal, according to the Journal.
People familiar with the matter told the Journal that the prosecutors want to know if American Media's payment violated the law, including campaign finance laws.
In a statement emailed to CNBC, American Media said: "American Media Inc., has, and will continue to, comply with any and all requests that do not jeopardize or violate its protected sources or materials pursuant to our first amendment rights."
McDougal was freed from her contract in April after suing American Media, alleging the company misled her about the terms of the contract.
McDougal's lawyer Davidson also represented porn star Stormy Daniels at the time she was paid $130,000 by Cohen for her silence about her own alleged affair with Trump.
Daniels, whose real name is Stephanie Clifford, is suing Trump and Cohen to void that nondisclosure agreement, which she signed shortly before the 2016 election. The White House has also denied Daniels' allegations of a tryst with Trump.
Daniels is also suing Davidson and Cohen in a separate suit, accusing them of colluding to protect Trump. Davidson's spokesman called the lawsuit "outrageously frivolous." Cohen's attorney in that lawsuit called Daniels' litigation a "publicity stunt."
--CNBC's Ryan Ruggiero contributed to this report.