Simmering tensions between Russia and Ukraine have soared unexpectedly in recent days after Moscow accused Kiev of attempting armed incursions into the Crimea peninsula it annexed in 2014.
Ukraine has fiercely denied the allegations but the war of words between the two sides has sparked fears of a wider conflict as fighting drags on between Kiev and pro-Russian rebels in two other eastern regions bordering Russia.
While the details of the incident remain extremely murky and with both sides making claims and counter claims, here is an analysis of what the latest flare up could mean:
What do the sides say?
Russia’s security service on Wednesday said it had thwarted “terrorist attacks” in Crimea over the weekend by Ukrainian military intelligence and beaten back armed assaults.
The FSB said one of its officers died in a firefight while arresting infiltrators and a soldier was killed in further clashes.
An irate President Vladimir Putin accused Kiev of “practising terror” and pledged not to let the death of the servicemen go unpunished.
Ukraine’s President Petro Poroshenko dismissed the claims as “fantasies” aimed at providing a “pretext for the next military threats” and put his troops on high alert.
Russian TV has aired footage of explosives and alleged Ukrainian military intelligence Evgen Panov, whom Moscow says was captured and confessed to plotting attacks. Ukraine says Moscow kidnapped Panov and has even blamed drunk Russian soldiers for the incident.
Whatever the truth of the incident, analysts say, far more telling is how both sides have reacted.
What could Russia gain?
Putin’s furious reaction fuelled fears that Russia might use the incident as a pretext to start a broader war against Ukraine. Moscow has long been accused of harbouring desires to conquer a land bridge to Crimea through Ukrainian territory.
But analyst Alexander Baunov from the Moscow Carnegie Centre wrote that any attempt to start a broader conflict “contradicts the logic” of Moscow’s recent moves aimed at tamping down tensions with the West over Ukraine and convincing Europe to drop punishing economic sanctions.
Instead the Kremlin appears keen to gain leverage over Kiev in any further negotiations on a stalled peace deal for the conflict in the east. Putin said the incident made a mooted fresh round of peace talks next month “senseless” and blasted Kiev as an unreliable partner for the West.
“Russia is clearly using what happened in Crimea as an attempt to raise more sharply with the West the idea of the Ukrainian leadership’s intractability,” Baunov wrote in an analysis Friday.
The FSB said Ukraine was aiming to destabilise the situation on Crimea ahead of nationwide legislative elections next month.
That has also led to allegations from some that the Russian leadership could be looking to ratchet up patriotic fervour and distract from a bruising economic crisis.