Sedlock was released from San Quentin State Prison about a year and a half ago for weapons violations.
ABC7 talked with a friend and roommate of Sedlock, who only wants to be identified as John O. He says the Vietnam veteran who was the target of a massive raid served in special ops.
"He has a little bit of issues from, I don't know if you want to call it post traumatic stress disorder; but right now he has a brain tumor, he's arthritic, he's on medications," John O. said.
When Sedlock is not taking his medication as prescribed, he has acted erratically, at times firing off guns outside his home. A neighbor who felt threatened complained to police.
That's when an arrest warrant and search warrant Tuesday night uncovered 45 firearms at the house, along with a cache of ammunition and eight explosive devices -- a total of 147 counts.
"He is a convicted felon and so that prohibitsunder California law from owning or possessing firearms of any kid and it is my understanding he had a lot of ammunition for different firearms," San Jose Police Ofc. Jose Garcia said.
ABC7 has learned Sedlock's long criminal history includes 15 convictions with incidents ranging from weapons violations to battery and alcohol use. His most recent 2007 arrest included driving with a blood alcohol level three times the legal limit with a loaded .357 Magnum.
The man who prompted a city block to close for 12 hours was released from prison last year. The Department of Corrections says Sedlock was on parole until May of this year and there were no known violations during that time.
John O. says he was aware of the large stash of firearms in the house but was never worried. He also says that Sedlock was aware that he was not supposed to have the weapons.
"He knows that but still defends the right to bear arms regardless of what anybody else says," John O. said.
Sedlock, 63, is being held at the Santa Clara County Jail. He could be arraigned as early as Thursday afternoon.