The six, who include "an important (PKK) member on the European level" were being held in the southern port city after being arrested as part of a probe into the group's financing, officials said.

The PKK, listed as a terrorist group by Turkey and much of the international community, took up arms for self-rule in the Kurdish-majority southeast of Turkey in 1984, sparking a conflict that has claimed 45,000 lives.

French authorities in March charged nine Kurds with terrorism offences following their arrest for allegedly recruiting fighters for the PKK.

French anti-terrorist police suspected the group had been recruiting and training young members at sites in France, including one training camp discovered north of Montpellier last year.

Police also suspected links with Kurdish groups in Germany, Belgium and Italy.