SOUTH MILWAUKEE, Wis. (MCT) — Police arrested a former girlfriend of the gunman who killed six people at a Sikh temple, saying an unauthorized gun was found in the home they once shared.

Misty Cook, a 31-year-old waitress and nursing student with reported ties to white supremacist organizations, was arrested Tuesday in a joint investigation with the FBI on suspicion of being a felon in possession of a firearm. Wade Michael Page, the gunman shot dead by police at the temple Sunday, had lived with her until moving to a separate residence a few weeks ago.