The U.S. Bureau of Prisons has opened an investigation into jailed pharmaceutical head Martin Shkreli’s activities behind bars after The Wall Street Journal reported that he was still running his company through a contraband cellphone. “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 told the Journal. “This allegation is currently under investigation.” The spokesperson declined to comment on Shkreli’s living conditions or whether he’s been separated from the general population. The newspaper previously reported that the 35-year-old, who is a little over a year into his seven-year sentence for securities fraud, is largely leading his former drug company from his jail cell in Fort Dix, N.J. He reportedly even fired the chief executive a few weeks ago over the phone. An attorney for Shkreli and the company, Phoenixus, did not respond to requests for comment.