1: Moscow ( CNN ) Ever since Vladimir Putin came to power , there have been killings of politicians , of human rights activists , of journalists . 2: But few who took part could have missed the symbolism , the real message the killers -- whoever they are -- sent by gunning down such a prominent Kremlin critic in the shadow of its towering walls . 3: A series of Kremlin critics have been murdered since Vladimir Putin came to power .
1: politicians , of human rights activists , of journalists 2: prominent Kremlin critic 3: A series of Kremlin critics