Turkey has remanded in custody five mayors from the country’s Kurdish-dominated southeastern region after accusing them of seeking to promote self-rule in the region.

Turkish courts remanded the mayors in custody on Sunday, after accusing them of seeking “to break up the unity of the state and integrity of the country,” the official Anatolia news agency said.

A court in the southeastern city of Diyarbakir reportedly placed under arrest the district of Sur’s co-mayors, Seyid Narin and Fatma Sik Barut, as well as the mayor of Silvan town, Yuksel Bodakci.

A court in the city of Hakkari also placed under arrest co-mayors Dilek Hatipolgu and Nuraullah Ciftci.

All of the mayors belong to the Democratic Regions Party (DBP), which has links to the country’s main pro-Kurdish political party, the Peoples’ Democratic Party (HDP).

According to Turkish media reports, the five mayors had been detained last week as Ankara was carrying out investigations into Kurdish-dominated regions in the country.

The local head of the HDP in Hakkari, Ismail Sihat Kaya, has also been detained.

The recent developments come a month after Turkey launched military operations against Kurdistan Workers’ Party (PKK) forces in the country’s southeast, as well as in northern Iraq. Reports say more than 800 PKK forces have been killed so far.

The PKK has been fighting the Turkish government and seeking self-rule since 1984. A shaky 2013 ceasefire was declared null by the PKK following the Turkish airstrikes against the group, narrowing the chances of the two sides reaching a deal in the near future.