Theo Lengyel, a founding member of the experimental rock band Mr. Bungle, has been arrested on suspicion of killing his girlfriend after human remains were found at a park near San Francisco, police said.

Alice “Alyx” Kamakaokalani Herrmann was last seen Dec. 3 in Santa Cruz County, where she lives, and became the subject of a missing person inquiry the following week, according to a statement from California’s Capitola Police Department.

“As the investigation progressed, it became clear that foul play was involved, leading to the identification of Theobald Lengyel as a suspect,” Capitola police wrote in a statement.

Lengyel, 54, was arrested Tuesday after investigators discovered human remains in a wooded area of Tilden Regional Park in Berkeley, the statement said. DNA confirmation is still pending but police believe it is Herrmann.

Jail records show Lengyel, of El Cerrito, California, was held without bail on one count of first-degree murder. He’s scheduled to appear in court Jan. 16.

A phone listing for Lengyel could not be found Thursday and it wasn’t known if he has a lawyer. The Santa Cruz County Public Defender’s Office didn’t immediately respond to an email asking if one of its attorneys was representing him.

Lengyel left Mr. Bungle in 1996 after playing saxophone, clarinet and keyboards on several recordings, including the band’s self-titled 1991 debut album and Disco Volante in 1995. He did not participate in any of the band’s recent reunion tours, which began in 2020.

Mr. Bungle was formed in Northern California’s Humboldt County in 1985 by high school friends including guitarist Trey Spruance, bassist Trevor Dunn and vocalist Mike Patton, who went on to perform with Faith No More. Mr. Bungle experimented with funk, heavy metal, electronic, jazz and other musical styles, gaining popularity during the alternative rock boom of the 1990s.

In a 2005 Q&A, Dunn said Lengyel left the band on bad terms, SF Gate reported.

“We unanimously decided to go on without him because he wasn’t growing with the rest of the band and we were running out of things for him to do. He got pissed off and I haven’t heard from him since,” Dunn wrote in response to a fan question.

Herrmann is a software engineer who was educated at the California Institute of Technology and worked at several San Francisco Bay Area companies over the years, according to her brother, Eric Herrmann. She is also an avid athlete who competed internationally in outrigger canoeing, he said.

“She’s very talented, loves music, very active outdoors,” Eric Herrmann told SF Gate on Dec. 19.