The gunman suspected of attacking a Waffle House in Tennessee lost his Illinois firearms license after exhibiting erratic behavior.

Authorities say Travis Reinking's weapons were turned over to his father, but the father simply returned the three rifles and a handgun to his son when the son decided to move out of state.

The case illustrates the difficulty of keeping guns away from mentally disturbed people and shows how easy it is for them to retrieve confiscated weapons.

Four people were killed in the attack on Sunday. Reinking was disarmed by a man at the restaurant and fled. He was captured Monday.

Illinois is one of the few states with a mechanism to allow firearms to be seized if someone's behavior constitutes a "clear and present danger."