The U.S. Bureau of Prisons opened an investigation into pharmaceutical wunderkind Martin Shkreli’s behavior behind bars, a bureau spokesperson said Friday.

The Wall Street Journal reported Thursday that Mr. Shkreli, 35 years old, is largely running his former drug company, Phoenixus AG, from his prison cell in Fort Dix, N.J., via a contraband smartphone. Mr. Shkreli is 16 months into a seven-year sentence for securities fraud.

“When there are allegations of misconduct, they are thoroughly investigated and appropriate action is taken if such allegations are proven true,” the prisons bureau spokesperson said. “This allegation is currently under investigation.”

The spokesperson declined to comment on Mr. Shkreli’s living conditions or on whether he had been separated from the prison’s general population. The department’s registry shows he is still housed at Fort Dix, a sprawling complex of about 4,000 male prisoners located an hour east of Philadelphia.

Benjamin Brafman, an attorney for Mr. Shkreli, declined to comment. Phoenixus didn’t respond to requests for comment.