IONE (AP) — Authorities say a Northern California prison doctor is recovering after an inmate attacked her.

The California Department of Corrections and Rehabilitation said in a statement Tuesday that 61-year-old inmate Robert Daniel Perry grabbed the 65-year-old doctor by the hair and started choking her during a medical appointment Monday at Mule Creek State Prison.

The doctor, a 20-year veteran of the corrections department whose name was not released, activated a personal alarm device and other medical staffers pulled her away from the inmate.

The statement says Perry cut a prison sergeant on the arm as guards restrained him. Staffers found a weapon made from two razor blades on him and found another weapon in his cell.

Perry is serving a 100-year sentence for making terrorist threats, stalking and attempted extortion.