Eight defendants, including police and journalists, were remanded on Tuesday to stand trial on charges relating to the murder of a prominent Armenian-Turkish journalist.

Hrant Dink, the founder of the bilingual Armenian-Turkish weekly newspaper Agos, was shot dead in an Istanbul street in January 2007.

Although a suspect was convicted, the case has been re-investigated several times amid concerns that police conspired to allow Dink's killing to happen.

According to a judicial source who spoke on condition of anonymity due to restrictions on talking to the media, the eight suspects were held on charges of membership of terror organization and "attempting to overthrow the constitutional order".

Ogun Samast, aged 17 at the time of the killing, claimed he murdered Dink for "insulting Turkishness" and was jailed for 23 years in 2011.

Since then, prosecutors have examined whether he acted alone.

In July 2014, the Constitutional Court ruled the original police inquiry had been an "ineffective investigation". Last December, another indictment was filed calling for the prosecution of 26 former police officers on charges of establishing an armed organization and dereliction of duty.

Recently, the investigation has been expanded to gendarmerie officers and claims linking the killing to the Gülenist terror cult that also perpetrated last July's attempted coup, have added a new dimension.