ANKARA, January 18. /TASS/. Six people suspected of being involved in the assassination of Russian Ambassador to Turkey Andrei Karlov have been brought to court on Wednesday to testify, Turkey’s Anadolu news agency reports.

The suspects were arrested by officers of the counter-terrorism department of the Ankara Directorate of security. Their testimonies will be added to the materials the prosecutor’s office has been collecting.

Russia’s Ambassador to Turkey, Andrei Karlov, was gunned down while he was delivering a speech at a photo exhibition. According to Turkey’s authorities, the attacker, an off-duty police officer named Mevlut Mert Altintas, was immediately neutralized by security forces. Russia’s foreign ministry officially declared the ambassador’s murder a terrorist attack, the Investigative Committee opened a criminal case labeling Karlov’s assassination an act of international terrorism.

Andrei Karlov was posthumously awarded the title of the Hero of Russia.