Six lawyers of U.S.-based Fetullah Gülen, accused of being the mastermind of the July 15 failed coup, have fled abroad, a police source said Friday.

The source, who spoke on condition of anonymity due to restrictions on talking to the media, told Anadolu Agency that police carried out an operation to detain 31 lawyers in the capital Ankara, 16 of whom were now in detention.

The lawyers representing Gülen who fled abroad were identified as Nurullah Albayrak, Hayrettin Açıkgöz, Mehmet Kadir Filizer, Hakan Yıldız, Melik Bayat and Mustafa Dokumacı, according to the source.

Efforts to catch nine other lawyers linked to Gülenist Terror Organization (FETÖ) remain ongoing, the sources said.

The suspects were accused of "attempting to prevent constitutional order through force and violence, and being members of the FETÖ/PDY armed organization".

Turkey has accused Gülen for ordering the foiled coup, which claimed more than 230 lives and injured nearly 2,200 others, and repeatedly demanded his extradition to Turkey to face trial.

Gülen has lived in self-imposed exile in Pennsylvania since 1999 and is also accused of a long-running campaign to overthrow the state through the infiltration of Turkish institutions, particularly the military, police, and judiciary, forming what is commonly known as "the parallel state."