Man charged with murder of SF social worker renews not guilty plea

SAN FRANCISCO (CN) — Wilfredo Tortolero Arriechi, the man accused of murder in the stabbing of a social worker at Zuckerberg San Francisco General Hospital in December, reentered his plea of not guilty at his secondary arraignment Monday.

Tortolero Arriechi, 35, was charged with murder on Dec. 8, 2025, after the stabbing of 51-year-old social worker Alberto Rangel.

Prosecutors say Tortolero Arriechi, who was a patient at the hospital’s HIV clinic, Ward 86, showed up at the clinic Dec. 4 to speak to his doctor, carrying a concealed knife. They claim he talked to Rangel, who asked him to leave. As the two men walked to the elevator, prosecutors say Tortolero Arriechi grabbed Rangel from behind and stabbed him multiple times.

Rangel died on Dec. 6, two days after the attack.

Following his arrest, Tortolero Arriechi was placed on psychiatric hold for three weeks. He pleaded not guilty in January and is being held in custody without bail.

On June 29, San Francisco Superior Court Judge Michael Rhoads ordered Tortolero Arriechi to stand trial, finding probable cause that he caused the death of Rangel.

At his secondary arraignment, Tortolero Arriechi appeared in an orange sweatsuit with his public defender, Sylvia Nguyen, and a Spanish-language interpreter. Assistant District Attorney Edward Mario also attended.

Tortolero Arriechi did not speak beyond confirming his name. He denied the accusations against him through his attorney.

Nguyen declined to comment after the hearing.

A representative for the district attorney’s office did not immediately respond to a request for comment.

In the weeks leading up to Dec. 6, staff at Ward 86 had reportedly warned the Department of Public Health, which runs the hospital, that Tortolero Arriechi was targeting a doctor at the clinic, according to reporting from the San Francisco Chronicle and DPH.

According to DPH, staff were concerned Tortolero Arriechi “seemed to be growing increasingly fixated on his physician” and had visited another clinic demanding to see him.

The audit showed Tortolero Arriechi sought out the doctor at the other clinic on the morning of the attack and promised to return until he got access, DPH said. He was expected to return to the clinic that afternoon, according to DPH, and the sheriff’s office sent a deputy to Ward 86 to provide security for the doctor. Despite this, Tortolero Arriechi was able to enter the hospital and access Ward 86.

His next court appearance is Sept. 29.

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