For the second time in around a week, several explosions have been reported in the Russian-occupied peninsula of Crimea – a sign Ukraine appears to be striking deeper into territory held by Vladamir Putin’s forces.
It’s a development that could potentially change the dynamic of the war.
Footage shared widely on social media purports to show the explosion at an ammunition depot near the village of Mayskoye in Crimea, the peninsula that has been occupied by Moscow’s troops since 2014.
It prompted the evacuation of 2,000 people in an eight-mile radius, and disrupted rail lines. Meanwhile, a Russian newspaper reported seeing smoke rising from a Russian airbase in Crimea.
There’s no immediate claim of responsibility, although two members of the Ukrainian president’s office hinted at the country’s involvement on Twitter in what they called “demilitarisation” – a mocking reference to a word Russia uses to justify its invasion.
The war is approaching its sixth month, but until last week this area of Russian territory appeared beyond the Ukrainian military’s reach.
Seven days ago, Ukrainian social media was abuzz with speculation about an attack on a Russian air base near seaside resorts Crimea.
Witnesses reported at least 12 explosions at Moscow’s Novofedorivka facility near the Black Sea resort of Saki, with Ukraine’s air force saying nine Russian jets were destroyed.
The fireballs, which killed one person and wounded 13, sent tourists fleeing in panic as plumes of smoke towered over the nearby coastline. They smashed windows and caused other damage in some apartment buildings.
The attacks are significant because they are far behind the frontline. Saki dangles off southern Ukraine and is around 150 miles away from the closest Ukrainian position.
The peninsula, used by Russia in February as one of its launchpads for its invasion, had until then been spared from the fighting.
So who or what was behind the attacks and why do they matter?
Who carried out attack, and was it long-range US weapons?
Ukrainian officials have stopped short of publicly claiming responsibility for the explosions last week.
Asked whether Ukraine was taking responsibility, presidential aide Mykhailo Podolyak told the Dozhd online television channel: “Of course not. What do we have to do with this?”
However, the Washington Post reported that Ukrainian special forces were behind the daring attack, according to a Kyiv official.
The question is then how the attack was carried out as the resort is out of the range of the missiles supplied by the US for use in the Himars systems.
The Ukrainian military has successfully used those missiles, with a range of 50 miles, to target ammunition and fuel depots, strategic bridges and other key targets in Russia-occupied territories.
Himars could also fire longer-range rockets, with a range of up to about 185 miles, that Ukraine has asked for.
But US authorities have refrained from providing them thus far, fearing it could provoke Russia and widen the conflict.
The explosions in Saki raised speculation on social media that Ukraine might have finally got the weapons.
But a US official told the Post that Ukrainian forces appeared to have carried out the attack without using a weapon provided by Washington.
Russia has blamed Tuesday’s explosion on sabotage, a rare admission that forces loyal to the Ukrainian government have hit its supply lines.
Crimea is used by Russia to reinforce its troops fighting in other areas of the war.
Will Russia retaliate?
Russia denied any aircraft were damaged in last week’s explosions – or that any attack took place – and Ukraine poked fun at Russia’s explanation that munitions at the Saki air base caught fire and blew up, a tone they repeated in the latest incident.
Last week, Russian authorities sought to downplay the explosions, saying all hotels and beaches were unaffected on the peninsula, which is a popular tourist destination for many Russians.
This week, they reported few wounded and no deaths in the latest incident.
Officials in Moscow have long warned Ukraine that any attack on Crimea would trigger massive retaliation, including strikes on “decision-making centres” in Kyiv.
Why is it important?
In any case, the attacks represent a dramatic escalation in the six-month long conflict, and the Russian response underscores the importance of the peninsula that Moscow annexed eight years ago.
If Ukrainian forces were responsible for the blasts, it would be the first known attacks on Russian military sites in Crimea.
A smaller explosion last month at the headquarters of Russia’s Black Sea Fleet in the Crimean port of Sevastopol was blamed on Ukrainian saboteurs using a makeshift drone.
In his nightly video address several hours after the first blasts, Ukrainian president Volodymyr Zelenskyy did not specifically mention the blasts but vowed to retake the peninsula, saying “this Russian war against Ukraine and against all of free Europe began with Crimea and must end with Crimea — its liberation”.