UPDATED | February 14, 2017 5:10 PM

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DALLAS (CBS11/AP) – A former Plano neurosurgeon has been found guilty of injury to an elderly person.  The jury read the guilty verdict after a short deliberation and moved to the punishment phase.

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The verdict means Christopher Duntsch, 44,  could be sentenced to five to 99 years or life in prison.

He also could be given probation.

The jury determined a botched spinal surgery on a patient named Mary Efurd was not simply malpractice, but malicious and reckless actions by Dr. Duntsch.

The defense tried to paint him as an inexperienced and poorly-trained doctor.

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Prosecutors had accused Duntsch of maiming four patients and causing the death of at least two between July 2012 and June 2013. They say Duntsch’s hands and surgical tools amounted to “deadly weapons” contended that Duntsch “intentionally, knowingly and recklessly” harmed up to 15 of his patients.

But the prosecution decided to focus on the case with Efurd — a first degree felony — injury to an elderly person.

Prosecutors said Duntsch said in a 2011 email to his girlfriend that he would “become a cold-blooded killer.”

But Duntsch’s attorneys argued that Duntsch was not a criminal but just a lousy surgeon committing malpractice in chaotic operating rooms in hospitals in Dallas and its northern suburbs. They also said the tone of the email to his girlfriend was unclear could have been meant as sarcasm.

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