The FBI is examining whether singer-songwriter Ryan Adams committed a crime by sending sexually-explicit messages to an underage fan.
Their investigation follows a report in the New York Times, in which the star was accused of sexual misconduct and abuse by several women.
One of them, identified only as “Ava”, showed reporters more than 3,000 explicit texts she said she exchanged with the star when she was 15 and 16.
His lawyer has rejected her claims.
“Mr Adams unequivocally denies that he ever engaged in inappropriate online sexual communications with someone he knew was underage,” Andrew B Brettler told the New York Times when the story broke on Wednesday.
An unnamed FBI source later told the newspaper it was looking into the allegations, and would seek to interview the woman, who is now 20, before deciding how to proceed.
The original New York Times story contained interviews with several women who said Adams had offered them help with their careers as a pretext for sex.
The story also contained interviews with musician Phoebe Bridgers and Adams’ ex-wife Mandy Moore, both of whom accused the star of being emotionally manipulative.
Adams’ initial response was to threaten legal action, in a tweet that said the newspaper was “going down”.
He quickly deleted that message and issued a statement calling the article “unsettlingly inaccurate,” and apologising to anyone he had hurt, “however unintentionally”.
The fallout has been swift and unforgiving.
The star’s forthcoming album, Big Colors, has been removed from release schedules; while three music companies have severed ties with the artist.
Amplifier company Benson, which was developing a Ryan Adams “signature model” said they were “saddened and surprised by the recent allegations” and had “decided to suspend our relationship” with the star.
Walrus Audio and JHS Pedals, who both made Adams-branded guitar pedals, said they would withdraw those models from sale.