The Kurdistan Workers' Party (PKK) announced a ceasefire on 13 April 2009, declaring they would only retaliate in self-defense. The ceasefire was encouraged by the electoral success of the Democratic Society Party (DTP) in the municipal elections of 2009. Then in May 2009, the president of the Kurdistan Communities Union (KCK) Murat Karayilan released a statement supportive of an eventual peace process. Later, the PKK prolonged the ceasefire on 1 June until 15 July 2009. On 15 July the DTP organized a manifestation in support of a peace process which was attended by tens of thousands of people in Diyarbakir, and the PKK again prolonged their ceasefire until 1 September 2009. The Human Rights Association (IHD), Freedom and Solidarity Party and the Labour Party also supported a potential peace process.