( CNN ) -- Thousands of angry demonstrators gathered in Paris Saturday to demand answers over the deaths of three Kurdish women activists found shot dead Thursday in mysterious circumstances . French police union spokesman Christophe Crepin said tensions were high at the protest , which some 15,000 people attended . Officers are expected to arrest a number of people for throwing objects at police , he said . Security was also stepped up at the Turkish Embassy in Paris . The French investigation into the slayings of the three Kurdish women -- named by Turkish officials as Sakine Cansiz , Fidan Dogan and Leyla Soylemez -- is ongoing . Read more : How Paris killings could renew Kurdish flashpoint . Cansiz , the oldest of the three women murdered in the Paris offices of the Information Center for Kurdistan , was famous for being a co-founder of the Kurdistan Workers ' Party , or PKK . Turkey , the United States and the European Union label the PKK a terrorist organization . There is still no clear evidence as to what lies behind the apparent assassinations . Read more : 3 Kurdish women political activists shot dead in Paris . But many in Turkey fear that the triple murder could derail delicate peace talks between the Turkish government and the PKK , which launched a guerrilla war against the Turkish state nearly 30 years ago . Kurdish activists have pointed the finger at possible Turkish involvement , while political leaders in Turkey have nodded to a possible feud within the PKK . Report : Turkey 's Kurdish conflict has turned more violent . Turkish Prime Minister Recep Tayyip Erdogan called on the French authorities Saturday to find the killers , the semiofficial Anatolian news agency reported . He also questioned why French President Francois Hollande had said the women were involved in talks with French officials . `` How can France hold talks with these people who are members of PKK that was also declared terrorist organization by the EU ? '' Erdogan is quoted as saying . Turkey had contacted French authorities in November about the presence of Cansiz , he said . The activist was previously detained in Germany in 2007 but Turkey 's extradition request was not met , he added . An autopsy Friday found that two of the women were killed by three gunshot wounds to the head and the third by four shots to the head , a spokeswoman for the Paris prosecutor 's office told CNN . Erdogan had previously suggested the deaths `` could be an internal settling of scores , or it could be an initiative that was taken to create an obstacle in the way of the new honest steps we are taking , '' according to the Anatolian news agency . But the PKK rejected suggestions that the killings were part of an internal feud . Read more : Turkish town on Syrian border deals with fighting , ethnic differences . In a statement published by the Firat News Agency , a pro-PKK web portal , the PKK 's Executive Committee blamed the murders on `` international powers and the Turkish gladio . '' `` Gladio '' refers to alleged shadowy paramilitary groups accused of carrying out acts of political violence on behalf of the Turkish state . `` It is not possible for this bloody attack to be carried out in a central place like this without the support of international intelligence services and states , '' the PKK added . The Turkish government issued a security warning to Turkish diplomatic missions in France and throughout Europe . Read more : Turkey police crack down on Kurds . Several hundred mostly Kurdish demonstrators gathered for a rain-soaked but peaceful protest in front of the French Consulate in Istanbul on Friday . A Kurdish lawmaker told CNN that the bodies of all three Kurdish activists were expected to be sent from France to Turkey for funerals . `` This could be a bullet that is shot in the head of the peace talks , '' said Sebahat Tuncel , a parliament member from the pro-Kurdish Peace and Democracy Party , speaking to CNN after Friday 's peaceful protest . But , she added , `` we should not suspend a possible peace process . '' Read more : Kurdistan officials hope Iraq will allow Turkish minister in . Kurdish activists accuse the Turkish government of decades of discriminatory policies against the country 's largest ethnic group . Turkish security forces have arrested thousands of Kurds in recent years on suspicion of terrorist activities . Last fall , the Turkish government initiated a new attempt at dialogue with Ocalan . The PKK leader is serving a life sentence in a prison on the Turkish island of Imrali . `` We knew achieving peace would be difficult , we knew there would be provocations ... we did not expect them to happen in France , '' said Tuncel , the Kurdish lawmaker . More than 40,000 people have been killed in one of the Middle East 's longest-running conflicts . Read more : Syria rebels , Kurdish militia discuss cease-fire . Journalists Dheepthi Namasivayam and Charles Pellegrin contributed to this report .
Demonstrators rally in Turkey to protest the killing of two French women activists . A Kurdish investigation into the triple murder continues . Turkey 's prime minister calls on the French authorities to find the killers . Speculation is rife over any link between the deaths and peace talks with the the European Union .