The man accused of killing a beloved veterinarian during a burglary last week pleaded not guilty during his first court appearance on Monday morning. He was scheduled to be arraigned last Friday, but it was delayed. Patrick O'Brien, 37, was arrested on June 15 and booked into jail on suspicion of one count of murder. According to San Diego Police, O’Brien got into an altercation with 88-year-old veterinarian Clark Kelly during an attempted burglary. Kelly was found with wounds to his head. He was taken to the hospital where he did not survive. Full story on CBS8.com: https://www.cbs8.com/article/news/crime/man-accused-of-murdering-veterinarian-in-court/509-119b23ad-7fc0-49d0-be7c-585af43c984d