Eric Uller, 50, is believed to have killed himself.
He was facing charges on multiple sexual crimes dating back to 1986 and was scheduled to appear in court Thursday morning in connection with the charges.
"The city was notified this morning that Eric Uller was found dead in his apartment," according to a statement issued by the city. "Initial indications are that it appears to be a suicide. The city was shocked to receive this news."
Uller was arrested after being accused of sexually abusing at least four teen boys years ago. Since his arrest, at least six more alleged victims came forward -- all are now adults.
Uller worked for the city of Santa Monica as a systems analyst before being placed on administrative leave.
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He was also a former volunteer of the Santa Monica Police Activities League from the 1980s to the 2000s.
Detectives said it appears he used a police persona with the minors.
"We believe Mr. Uller befriended these kids, and he targets mainly boys, and we know that," said Lt. Todd Deeds of the Los Angeles County Sheriff's Department.
Investigators said some of the alleged crimes happened on site.
Uller came under investigation by the Los Angeles County Sheriff's Department's Special Victims Bureau in June, when detectives received information from the Santa Monica Police Department, which received an anonymous tip about the alleged lewd acts.
The city said it would continue to see its independent investigation through. Anyone with information was urged to reach out directly to the independent counsel at https://www.aalrr.com/contact-cerritos or (562) 653-3200.
City News Service contributed to this report.