Diyarbakir: Turkey has removed local mayors deemed to support Kurdish militants and appointed new administrators in two dozen municipalities mostly in the largely Kurdish southeast, a provincial governor’s office said on Sunday.

The 24 municipalities were run by local associates of the pro-Kurdish opposition Peoples’ Democratic Party (HDP), the third largest party in the national parliament, the Diyarbakir governor’s office said.

President Tayyip Erdogan said on Thursday that the campaign against the Kurdistan Workers Party (PKK) militant group, which has waged a three-decade insurgency for Kurdish autonomy, was Turkey’s largest ever and that the removal of civil servants linked to them was a key part of the fight.

The crackdown comes as Ankara also pushes ahead with a purge of tens of thousands of supporters of U.S.-based Muslim cleric Fethullah Gulen, accused by Turkey of orchestrating an attempted coup in July. Gulen denies any involvement.

The mayors of four other municipalities, three from the ruling AK Party and one from the nationalist MHP opposition, were also removed on Sunday over alleged links to Gulen.

Erdogan and the government view the HDP as an extension of the Kurdish PKK militant group. The HDP denies direct links and says it promotes a negotiated settlement to the insurgency.

There were internet and phone outages in several areas across the southeast on Sunday, local residents said, although the reason was not immediately clear.

On Friday, police detained dozens of people and used water cannon to disperse several hundred teachers demonstrating against their suspension from classrooms in the main regional city of Diyarbakir.

More than 40,000 people, most of them Kurds, have died since the PKK launched its insurgency against the Turkish state in 1984. The PKK is regarded as a terrorist organisation by Turkey, the United States and the European Union.