Istanbul (CNN) -- Several hundred mostly Kurdish demonstrators gathered for a rain-soaked protest in front of the French Consulate in Istanbul on Friday, a day after three Kurdish political activists were found shot dead in Paris.
The crowd, made up of Kurdish nationalists and left-leaning Turkish political parties, chanted "Sakine Cansiz is immortal."
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.
Demonstrators also chanted "Long live Apo," hailing Abdullah Ocalan, the jailed leader of the PKK.
A human wall of Turkish riot police dressed in helmets and gas masks guarded the entrance of the French Consulate, as employees inside watched nervously through a window.
The French investigation into the slayings of the three Kurdish women -- Cansiz, Fidan Dogan and Leyla Soylemez -- is ongoing.
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.
There is still no clear evidence as to what the motivation behind the apparent assassinations could be.
Kurdish activists have pointed the finger at possible Turkish involvement, while political leaders in Turkey have nodded to a possible feud within the PKK.
"This 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," said Turkish Prime Minister Recep Tayyip Erdogan, according to the semiofficial Anatolian news agency.
On Friday, the PKK rejected suggestions that the killings were part of an internal feud.
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 throughout Europe.
"We asked the French to step up security around our diplomatic missions in France," said Selcuk Unal, a spokesman for the Turkish Foreign Ministry.
"And finally we asked our missions in France and Europe ... to be alert to any kind of provocation or possibility of provocation stemming from this incident."
Meanwhile, a Kurdish lawmaker told CNN that the bodies of all three Kurdish activists were expected to be sent from France to Turkey for funerals, though she added that an arrival date has not yet been set.
"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."
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. More than 40,000 people have been killed in one of the Middle East's longest-running conflicts.
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.