MOSCOW (AP) — Colleagues of renowned investigative journalist Anna Politkovskaya are marking the 10th anniversary of her killing by demanding that investigators track down its mastermind.

Politkovskaya, noted for her criticism of Kremlin policies in Chechnya and of human rights violations there, was gunned down in the elevator of her Moscow apartment building on Oct. 7, 2006.

In 2014, a court in Moscow convicted the gunman and three other Chechens involved in the killing along with a former Moscow policeman who was their accomplice. Another former police officer involved in the killing made a deal with authorities that allowed him to qualify for a reduced sentence in exchange for cooperation with investigators.

Politkovskaya's newspaper, Novaya Gazeta, on Friday strongly criticized the investigators for failing to determine who ordered the killing.