SAN FRANCISCO—A man who allegedly posed as a nurse practitioner and worked in a medical clinic for four months, was arrested and charged with practicing medicine without a license and identity theft.

Chad Brian Litz, 39, allegedly volunteered as a nurse practitioner at San Francisco City Impact, a free medical and dental clinic serving residents of the Tenderloin District. While volunteering, Litz used a forged certificate from the American Academy of Nurse Practitioners, as well as other fraudulent materials.

According to court documents, Litz allegedly treated at least 28 patients with little supervision and prescribed controlled substances to two of them. The fraud was discovered by clinic volunteers who reported Litz to the state California Department of Consumer Affairs.

He was arrested on March 10 in Tampa, Florida, as he was leaving from a cruise ship. He was arraigned and pleaded not guilty  in court on Thursday, March 30 to four felony counts of practicing medicine without a license and one felony count of identity theft.

He remains in custody, with a bail set at $65,000, and is scheduled to return to court on Tuesday, April 11 for a preliminary hearing.

Officials are asking anyone who suspects they may have been treated by Litz at San Francisco City Impact at 230 Jones St. to contact Investigator Andrea Todd at the Department of Consumer Affairs at (510) 888-7072.