From his Wikipedia Page:

After he retired, he was very prolific in spreading awareness of the child kidnapping and subsequent ritual abuse.

He also investigated a child molestation trial in Manhattan Beach, California. In a 1995 conference in Dallas, Gunderson warned about the supposed proliferation of secret occultist groups, and the danger posed by the New World Order, an alleged shadow government that would be controlling the United States government.[9] He also claimed that a "slave auction" in which children were sold to men had been held in Las Vegas, that four thousand ritual human sacrifices are performed in New York City every year, and that the 1995 bombing of the Alfred P. Murrah Federal Building in Oklahoma City was carried out by the US government.[9] Gunderson believed that in the United States there is a secret widespread network of groups who kidnap children and infants, and subject them to ritual abuse and subsequent human sacrifice.

Isn't it interesting that at the bottom it was added,

On July 31, 2011 Gunderson's son reported that his father had died from cancer.

Does anyone know more?