FREMONT (CBS/AP) — A Fremont hospital nurse faces charges that he sexually assaulted two female patients.

Jon Jeffrey Quianzon pleaded not guilty on Thursday to sexual battery and sodomy in connection with the alleged attacks at Washington Hospital in Fremont.

Police said another hospital employee witnessed the 31-year-old Quianzon assaulting a woman who was brought in on June 10. The alleged victim was a 21-year-old Hayward woman.

Fremont police spokeswoman Geneva Bosques says during the subsequent investigation, detectives learned that another patient had accused Quianzon of sexually assaulting her in 2009.

Quianzon’s attorney, Frank Leidman, said a hospital investigation into the 2009 complaint cleared his client of any wrongdoing.

Quianzon is no longer employed at the hospital.

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