Highmark Inc.'s Kenneth R. Melani, CEO of Pennsylvania's largest health insurer, has been fired, Highmark announced Sunday. Melani 58, had been on unpaid leave from the Pittsburgh insurance company, where he was also president, following his arrest on charges stemming from a fist fight. His termination followed a meeting Sunday of Highmark's board of directors. Melani was charged with simple assault and criminal trespass. Melani had led Highmark since 2003. The board, however, is "moving forward to identify a long-term successor to the CEO position," Baum said in the company's statement. The Highmark Board of Directors has named Board Chairman, Dr. J. Robert Baum, Highmark's interim CEO.