Turkish authorities have detained more than 20 police officers in raids over an alleged plot to overthrow the government of President Recep Tayyip Erdogan.
Police conducted early morning raids in 16 cities, including Istanbul as well as the western province of Izmir, and detained at least 20 officers, NTV television reported.
Among those arrested was Yakup Saygili, the former chief of the police anti-fraud unit, it added.
It was the fourth such wave of raids since July as the government cracks down on what Erdogan has described as a "parallel state" within security forces.
Arrest warrants were issued for at least 34 officers accused of offences including illegally eavesdropping on top officials and attempting to overthrow the government.
Since July, dozens of police officers have been arrested and placed in custody on suspicion of forming a criminal organisation and wire-tapping hundreds of people, including Erdogan.
Erdogan has long accused followers of United States-based Muslim cleric Fetullah Gulen of establishing a "parallel state" by using his influence in police and the judiciary and of concocting a vast corruption scandal.
Erdogan on Thursday moved from the office of prime minister to president after his election victory, with close ally and former foreign minister Ahmet Davutoglu becoming premier.