STOCKHOLM (AP) — The father of Norwegian mass killer Anders Behring Breivik says he fears his son is becoming even more extreme and dangerous in prison.

In his first news conference since the July 22, 2011, attacks that killed 77 people, Jens Breivik said Thursday he had requested to visit his son at the Oslo area prison where he is serving a 21-year sentence that could be extended indefinitely. But the convicted terrorist and right-wing fanatic rebuffed him in a letter, saying his father had to adopt a “fascist” ideology for them to have any contact.