What Happened: Russia's Defense Ministry attributed a series of explosions at an ammunition depot in Russian-annexed Crimea to Ukrainian saboteurs, The New York Times reported Aug. 16. While Ukraine has not officially taken responsibility for attacks on Russia, a senior Ukrainian official, on the condition of anonymity, said an elite Ukrainian military unit operating behind enemy lines was responsible for the blasts.

Why It Matters: Russia's attribution of the attack to Ukraine is a shift from its noncommittal stance seen following a similar attack in Crimea last week on a Russian airbase. However, like the attack last week, Russia has not retaliated against Ukraine, which strengthens the precedent that Ukraine can strike Russia with few consequences. This inaction undermines the credibility of Russia's threats to retaliate or escalate the war over Ukrainian attacks on Russian-annexed territory, and this lack of credibility will only grow if this pattern continues following the possible Russian annexation of additional Ukrainian territories in the Donbas region and southern Ukraine. Like last week's attack, it was not immediately clear how saboteurs had triggered the blasts, though Russian state media speculated that Ukraine may have used small drones to bomb the ammo depot and other facilities. Ukraine likely will seek to continue attacks in Russian-occupied areas, including Crimea, as part of an offensive in southern Ukraine.

Background: The exploding ammunition from the strike damaged civilian infrastructure, including a power plant and a railway track. On Aug. 10, a series of explosions occurred at the Saki military airfield in the village of Novofedorivka on the southwestern coast of Crimea in an apparent attack by Ukrainian forces, but Ukraine did not officially accept responsibility for the attack.