The co-mayors of the largest city in Turkey's predominantly Kurdish southeast have been detained for questioning as part of a "terrorism" investigation, according to Turkish media reports.

The state-run Anadolu Agency reported that anti-terrorism police took Gultan Kisanak into custody late on Tuesday at the city's airport. The second politician, Firat Anli, was held at his home.

The agency cited an ongoing probe into the outlawed Kurdistan Workers' Party (PKK) as the reason for their detentions, without providing further details.

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Kisanak is a member of Turkey's legal pro-Kurdish Peoples Democratic Party, which the government accuses of being the political wing of the PKK. The party denies the accusation.

Earlier on Tuesday, she had testified in front of a parliamentary committee investigating Turkey's failed July 15 military coup.

Last month, Turkey removed tens of mayors in the region accused of links to PKK, replacing them with state-appointed trustees in a major shake-up under emergency powers enacted after the coup attempt.

The autonomy-seeking PKK abandoned a two-year ceasefire in July, reigniting a conflict that has claimed more than 40,000 lives since 1984.

The government has accused the PKK of a series of attacks in the southeast of Turkey in recent weeks.

Turkey, the European Union and the United States have labelled the PKK a "terrorist" group.

Source: Agencies