SAN CARLOS (CBS SF) — A Redwood City man was arrested Tuesday in San Carlos on suspicion of possessing illegal drugs but may have been operating as a dentist without a license, state and county authorities said Thursday.

Joseph Hirsch, 59, was arrested at about 7 a.m. at Thermo Dental at 663 Old County Road when task-force agents served a search warrant at the business, according to the San Mateo County Narcotics Task Force.

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An investigation started in January and on Tuesday investigators searched the business and allegedly found drugs and equipment typically used to manufacture drugs.

Investigators said they also allegedly found a crude dental office consisting of a dentist’s chair, x-ray machine and dental tools.

It appears Hirsch has a denture manufacturing business but was allegedly operating as a dentist as well, California Department of Consumer Affairs Detective Ryan Blonien said.

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According to Blonien, Hirsch never had a dentist’s license but was allegedly acting as a dentist in fitting patients for dentures.

Hirsch was taken to the county jail on suspicion of possessing a controlled substance, manufacturing a controlled substance, being a felon in possession of ammunition and possessing metal knuckles, according to jail records.

Hirsch has not been arrested for allegedly working as a dentist without a license but an investigation hasn’t been completed, Blonien said.

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