SACRAMENTO (CBS News) — Joseph James DeAngelo, the ex-police officer suspected of being the notorious “Golden State Killer,” appeared in court for an arraignment Friday.

Police say DeAngelo is the serial predator who killed 12 and raped nearly 50 in the 1970s and 80s in California. He was arrested Tuesday at his suburban Sacramento home.

A judge read the charges against DeAngelo, who appeared in the courtroom in a wheelchair wearing an orange prison jumpsuit. Another court date was set for May 14.

DeAngelo was handcuffed to the wheelchair, looking frail and weak and barely able to speak above a whisper. A sharp contrast to the man who went on a terror rampage.

DeAngelo is on suicide watch in the psychiatric ward of the county jail and has been quietly talking to himself, said Sacramento County Sheriff Scott Jones. Authorities said more charges are likely to be filed later.

Police in the central California city of Visalia said Thursday that DeAngelo is now a suspect in a 13th killing and about 100 burglaries that occurred while he was a police officer in the neighboring farm town of Exeter from 1973 to 1976.

Media and family members of victims were gathering in the packed courtroom ahead of the arraignment, CBS Sacramento’s Lemor Abrams reported via Twitter.

CBS2’s Tom Wait reported from the courthouse and DeAngelo’s neighborhood.

He also spoke to Keith and Ken Smith whose sister, Katie Maggiore, was believed to be one of DeAngelo’s first victims.

“It was very surreal,” said Ken, “it’s hard to explain the feelings that overcome you.”

Said Keith, “The hardest thing for me is when the judge read the names [of the victims]. Then it was real.”

Katie would have turned 60 this year. Her brothers said they felt her presence in the courtroom.

Meanwhile, DeAngelo’s next-door-neighbor wondered how he ended up in a wheelchair Friday.

“From what I know,” said Nathan Harvey, “he is a very active, healthy man who enjoyed working. The Joe I know, was actually a really good neighbor. No one would expect he would be any different from any other neighbor I have.”

MORE NEWS: Stars Show Out To Celebrate Emmy Nominations Ahead Of Big Show

© 2018 CBS Interactive Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.