The brutal assassination in central Paris of three Kurdish militants, including a founder member of the separatist group the PKK, has sent a shockwave through France and Turkey.

The three women were found shot in the head at a Kurdish "information centre" a few steps from the Gare du Nord in the early hours of yesterday. The attack is believed to have occurred at least eight hours previously.

Police broke down the bloodstained door of an office in a classic Parisian apartment block and discovered what one called a scene of "cold-blooded butchery, almost certainly an execution". Two of the women had been shot in the back of the head and the other in the forehead and chest.

Turkish government officials and French intelligence sources blamed faction-fighting within the PKK (Kurdistan Workers' Party) for the killings. They said the murders were probably connected to exploratory talks between the Turkish Government and the imprisoned PKK leader, Abdullah Ocalan, which were revealed in the Turkish press on Wednesday.

The negotiations were said to have produced a "road-map" to end the 30-year-old civil war in southeastern Turkey in which 40,000 people are believed to have died. One of the victims - and possibly the principal target - was Sakine Cansiz, in her late 50s, a long-time associate of Ocalan and a founder member of the PKK, which was established in 1978.

In recent years Cansiz had apparently fallen out with the PKK's splintered leadership, but remained a supporter of the Kurdish separatist cause.

Yesterday President Francois Hollande said: "This is a horrible crime [involving] three people, one of whom I knew well because she often came to see political leaders [in France]." It is believed that Hollande was referring to Cansiz.

Police said there was no sign of a break-in, suggesting that the three women may have opened the door to whoever killed them. The other victims were named as Fidan Dogan, 28, a Brussels-based official of the Kurdistan National Congress (KNK), a support-group for the PKK, and Leyla Soylemez, 25, who ran a Kurdish youth association in Paris.

Soylemez's boyfriend became anxious after she failed to come home or answer her cellphone. He went to the Kurdish Information Office and found traces of blood on the outer door. He called police who broke down the first-floor door and found the bodies.

Political assassinations are rare in Paris or any other Western European capital. The French Interior Minister, Manuel Valls, visited the crime scene yesterday. "Three women have been murdered, doubtless executed," he said. "This is a very serious event. The French authorities will do all in their power to throw light on this completely intolerable act."

There were a number of theories yesterday about who was responsible for the attack. Cansiz had been granted political asylum in France after being imprisoned in Turkey, although she did not live permanently in Paris. Kurdish officials in Paris dismissed the "internal quarrel" theory, instead blaming agents of the Turkish Government or French-based activists from the Turkish extreme right.

Once news of the killings got out, more than 300 Kurdish exiles demonstrated and waved Kurdish flags in the rain close to the murder scene. They chanted, "Turkey assassins. Hollande is their accomplice," and, "We are all in the PKK."

The PKK was founded in 1978 by Ocalan and Cansiz, among others, to campaign for a Marxist Kurdish state in southeastern Turkey and the Kurdish-populated areas of Iran, Iraq and Syria. It began a military campaign in the mid-1980s after repression by the junta that then ruled in Ankara. It is classed as a terrorist organisation by Turkey, the United States and the European Union and Ocalan has been in a Turkish jail since 1999.

According to reports in the Turkish press on Wednesday, the peace talks between Ankara and Ocalan would involve a ceasefire in return for release of prisoners and official recognition of the Kurdish language and culture. Yesterday's murders, according to the Turkish Government and French intelligence sources, may have been intended to discredit or destroy these talks.

The PKK has a history of bloody settlement of internal battles, including, allegedly, murders on foreign soil. A Turkish political commentator, Emre Uslu, who once worked in Turkey's counter-terrorism unit, suggested the killings might have been ordered by the PKK leadership, pointing out that Cansiz led a faction that had opposed Ocalan's peace moves in the past. But a Kurdish official in Paris, Eyup Doru, was convinced the Turkish Government was responsible. "The work [these women] were doing, attracting attention to repression by the Turkish authorities, doubtless embarrassed the Government."

This theory was dismissed by French intelligence sources.

The victims

Sakine Cansiz
As a founding member of the militant Kurdistan Workers Party (PKK), Sakine Cansiz was the first senior female member of the organisation. Cansiz led the Kurdish protest movement out of Turkey's Diyarbakir prison in the 1980s. She later served as a commander of the women's guerrilla movement in Kurdish areas of northern Iraq.

Fidan Dogan
The Paris representative of the Brussels-based Kurdistan National Congress (KNC) political group worked in the information centre, and was responsible for lobbying European Union diplomats on behalf of the PKK.

Leyla Soylemez
Described as a "young activist" for the KNC, she is believed to have worked on diplomatic relations and as a women's representative on behalf of the PKK.

- Independent