Martin Shkreli was sentenced to seven years in prison for fraud. He told his family, “I love you. I miss you. Please don’t worry about me.” USA TODAY

Martin Shkreli, the controversial pharmaceutical entrepreneur who , is now facing a federal investigation into his behavior in prison.

The Bureau of Prisons has opened an investigation into Shkreli after that he was secretly leading his pharmaceutical enterprise using a cell phone behind bars.

“When there are allegations of misconduct, they are thoroughly investigated and appropriate action is taken