ISTANBUL (AP) — Kurdish militants who have waged a 40-year insurgency in Turkey declared a ceasefire on Saturday in what could mark a significant boost to President Recep Tayyip Erdogan’s government, two days after their imprisoned leader called for the group to disarm.

Abdullah Ocalan’s appeal raised the prospect of an end to a conflict between Turkey and the PKK that since the 1980s has killed an estimated 40,000 people.

The 75-year-old militant leader Abdullah Ocalan has spent a quarter of a century in jail after leading his Kurdistan Workers Party (PKK) to take up arms against the Turkish state to fight for a Kurdish homeland.