ISTANBUL (Reuters) - Turkish authorities have detained 88 people over suspected links to the outlawed Kurdistan Workers Party (PKK), the Interior Ministry said on Friday.

The operation across seven provinces was carried out to prevent possible attacks on the fourth anniversary of protests by Kurds that killed and wounded dozens of people across the country, the ministry said in a statement.

The Oct. 6-7, 2014 demonstrations were sparked by Kurds’ demand that the government do more to protect the Syrian Kurdish town of Kobani from Islamic States militants.

The PKK, considered a terrorist organization by the United States, Turkey and the European Union, has waged an insurgency against the Turkish state since 1984. Violence in the largely Kurdish southeast has escalated since the collapse of a ceasefire in 2015.

On Wednesday, seven Turkish soldiers were killed and three others wounded after a roadside bomb in the southeastern province of Batman was detonated by Kurdish militants, security sources said.

Turkey has in recent months also conducted strikes on PKK bases in northern Iraq, especially the insurgents’ stronghold in the Qandil mountains, where Ankara has also threatened to carry out a ground offensive.