Orhan Miroglu, deputy chairman of the Democratic Society Party (DTP), was detained after he referred to Ocalan as "sayin" -- a word that means esteemed or honourable but also doubles for "mister" in Turkish, the report said.

Ocalan, serving a life sentence for treason since 1999, is the leader of the outlawed Kurdistan Workers' Party (PKK), which has waged a bloody separatist campaign in the mainly Kurdish southeast since 1984. It is listed as a terrorist group by Turkey and other countries.

DTP members have increasingly become the target of judicial action in recent weeks for supporting the PKK.

Miroglu made the speech at a rally in Ankara, which was part of festivities this week to celebrate the Kurdish New Year, Newroz Day, the biggest Kurdish festival.

He was to be released or formally arrested after being questioned.