Updated

Authorities say an ex-convict arrested on a gun charge became radicalized during his incarceration and expressed a desire to join the Islamic State group.

The charges announced Thursday by federal prosecutors in Richmond against 28-year-old Casey Spain do not include any terror-related counts. Instead, he is charged with being a felon in possession of a firearm.

In an FBI affidavit, authorities say Spain, while serving a seven-year prison sentence, had the Islamic State flag tattooed on his back.

The FBI kept him under surveillance after his release from prison earlier this month. Undercover informants said Spain frequently expressed his desire to travel overseas to join the Islamic State and to obtain a gun.

He was arrested Thursday after prosecutors say he tried to buy a gun in an FBI sting.