A court ordered that Hanefi Avci, former chief of police in the western city of Eskisehir, be remanded in custody after being detained on Tuesday in an investigation into the Revolutionary Headquarters group blamed for attacks on state targets.

Avci leapt to prominence in the Turkish media in recent weeks over a book in which he alleges that members of an Islamic movement run by preacher Fethullah Gulen had infiltrated the police and courts.

The book also argues there is a lack of evidence to justify the trial of alleged members of a clandestine group known as Ergenekon which is accused of plotting to overthrow Prime Minister Tayyip Erdogan's government.

Erdogan's opponents suspect his AK Party of harboring an Islamist agenda at odds with modern Turkey's secularism. The party denies any such designs and depicts itself as a democratic, conservative party akin to Europe's Christian Democrat parties.

Secularist critics say followers of the Gulen movement have gained influence by infiltrating many areas of the state apparatus and have ties to the ruling AK Party.

Gulen lives in self-imposed exile in the United States. His followers have created a network of schools and universities across Turkey, Central Asia and the Balkans.

Anatolian said Avci was being held at Metris jail in Turkey's largest city while police continue their investigation.

The former police chief has denied all allegations against him. Police also searched his home in Eskisehir province.

“A man who fought terror for 40 years is now in detention on terror charges,” Turkish media reported him as saying when he was detained.

A senior member of the militant group was killed in a police siege in Istanbul last year. It was believed to be behind attacks on a military barracks and a building housing offices of the AK Party.

Media reports say 17 members of the Revolutionary Headquarters group were detained in police raids in several provinces last week.