 Later in 2006, Abdullah Öcalan denied the accusations and stated in his book that both Mahsum Korkmaz, the first supreme military commander of the PKK, and Engin Sincer, a high ranked commander, likely died as a result of internal conflicts and described the perpetrators as "gangs".The leaked reports, however, had revealed the authoritarian personality of Öcalan who had brutally suppressed dissent and purged opponents since the early 1980s.According to David L. Philips, up to sixty PKK members were executed in 1986, including Mahsum Korkmaz, who he believes was murdered on 28 March 1986.