A peshmerga commander Shafik Chavshin, speaking to the Kurdistan Regional Government (KRG)-based Rudaw news agency, said that the PKK's official Syrian branch, the Democratic Union Party (PYD) and its armed People's Protection Units (YPG) made a huge mistake that resulted in the failure of the Sinjar operation. Chavshin said that the peshmerga decided not to enter the city center after defeating Islamic State of Iraq and al-Sham (ISIS) militants around the city. But he complained about the YPG fighters who announced that they entered the city center. He said: "YPG fighters were in a hurry to announce their entrance to the city although it was not a part of the plan. Besides doing nothing, they have undermined our struggle to capture the city." He underlined that Kurdish fighters must gain control of Mosul's western parts to capture Sinjar completely.After ISIS captured Mosul, Anbar and Sinjar last summer, Kurdish fighters, including the PKK, YPG and peshmerga units, united against the militants. However, it is a well-known fact that the PKK and KRG administration have a troubled relation over their policies on Turkey. While the KRG has established good relations with Turkey, the PKK continues to organize terror attacks in Turkey and motivates Kurdish people to challenge the government despite the ongoing reconciliation process. The PYD, which has been operating in Syria as the PKK's branch for decades, has sent YPG fighters to Iraq. However, Chavshin was disappointed with their presence and said: "I do not understand what YPG fighters are doing in Sinjar. It is a part of the KRG and there must only be peshmerga fighting there."According to Rudaw, peshmerga forces along with YPG fighters decided to capture Beac and Tal Afar, which neighbor Sinjar. After peshmerga forces were on their way to capture Beac and Tal Afar, YPG fighters entered Sinjar, the news agency reported.Another peshmerga commander, speaking on the condition of anonymity to Rudaw, said that "the entrance to Sinjar disturbed the U.S. since they had not been informed. Therefore the U.S. lessened the airstrikes." Despite statements by these commanders, the Sinjar Front's Commander Bahram Arif Yasin rejected the claims and said that "the operation in Sinjar was carried out after informing the [KRG] President [Masoud Barzani]."Kurdish fighters have been battling ISIS militants for 20 days and made advances on the ground with the help of the U.S.-led anti-ISIS coalition. After ISIS captured Sinjar, hundreds of Yazidis were massacred since they were considered infidels and thousands of them have fled to Turkey and the KRG while many of them have been trapped in the Sinjar Mountains for weeks.