It was not immediately clear who killed the women, who belonged to the Kurdistan Workers Party, or PKK, a group that Turkey and its Western allies, including the United States and the European Union, consider a terrorist organization.
The slayings came as Turkey was holding peace talks with the group to try to persuade it to disarm. A Turkish lawmaker claimed the women were slain in a dispute between PKK factions, while some Kurdish protesters and a Kurdish lawmaker in Turkey claimed the Turkish government was involved.
Turkey's Anadolu news agency identified one of the victims as Sakine Cansiz, a founding member of the PKK.
The conflict between the PKK and Turkish troops has claimed tens of thousands of lives since 1984, when the rebels - who are seeking self-rule for Kurds in southeast Turkey - took up arms.
French Interior Minister Manuel Valls, who visited the pro-Kurdish center in Paris where the bodies were found, said the deaths were "without doubt an execution." He called it a "totally intolerable act."
RTL radio reported that all three women were shot in the head, but French police would not immediately confirm the report.
Emotions mounted as hundreds of Kurds filled the street in Paris outside the Kurdistan Information Center. Police erected barricades to try to contain the crowd. Some people waved Kurdish flags while others chanted angrily against the Turkish government.
An online site for Kurdish youth called on all Kurds and "friends of Kurds to come to Paris." The site, jeunessekurde.fr, showed three photos of the slain women. It identified the other two as Fidan Dogan, who reportedly was chief of the information center, and Leyla Soylemez.
Kurds make up more than 20 percent of Turkey's 75 million people.
The three women were alone at the center on Wednesday and were unreachable by telephone, said Leon Edart, an official of the Federation of Kurdish Associations of France.
Friends went there after midnight and saw traces of blood on the door which they then broke down, discovering the bodies, he said.
Police and firemen reached the bodies about 1:30 a.m. Thursday, a police official told The Associated Press. He spoke on condition of anonymity because he was not authorized to give his name in keeping with policy.
In Turkey, Selahattin Demirtas, the leader of a Kurdish political party in Turkey's parliament, called on the French government to shed light on the killings "without delay" and in a way that "leaves no room" for doubt.
"We want it to be known that that these assassinations which were carried in the busiest area of Paris cannot be covered up," Demirtas said.
Huseyin Celik, the deputy chairman of Turkey's ruling party, said the attack appeared to be the result of "an internal feud" within the PKK, but did not provide any evidence to back his statement.
Celik also suggested the slayings were an attempt to derail the peace talks.
The PKK does have a history of internal executions. While many Kurdish activists and militants were victims of extra-judicial killings blamed on Turkish government forces in the 1990s, it's not known whether they also targeted any exiled Kurds in Europe.
Gultan Kisanak, a joint leader of the Kurdish political Party, Peace and Democracy Party, called Cansiz "an idol of the Kurdish people and Kurdish women" and rejected the possibility of an internal feud within the PKK.
"She was a hero and true revolutionary who would not even waste a minute for the good of the Kurdish women," she said.
"This is a trap placed on the path to a solution of the Kurdish problem, it is a political assassination," Kisanak said.
"How dare they present the murder of a revolutionary on internal strife without any evidence?" she said in response to Celik's comment.
In the streets of Paris, the protesters blamed Turkey.
"Where are French? Where is that solidarity? I think that the state of Turkey did this," said one man in the Paris crowd, identifying himself only as Ali.
Turkey frequently accuses, France, Germany and the Netherlands - home to large numbers of Kurds from Turkey - of supporting the PKK, failing to extradite wanted militants and of not backing Turkey's "fight against terrorism."
Turkish officials say the PKK raises funds through extortion or other criminal activities in European countries that have a large number of Kurdish immigrants.
France has a large Kurdish community concentrated in the Paris region and French police have occasionally arrested Kurds suspected of illegally financing the PKK.
(Copyright 2013 by The Associated Press. All Rights Reserved.)