KIEV/MOSCOW — An explosion on Saturday morning hit a controversial bridge linking Crimea with Russia, which appears to have partially collapsed.

The blast happened at around 6 a.m. local time, sparking a fire on several wagons of a train on the adjacent railway bridge, according to the Russian National Anti-Terrorism Committee.

Images shared on social media purported to show fire and damage to the bridge, with one section in the water.

Ukrainian officials have provoked the ire of Russia by joking about the blast, without directly claiming responsibility.

The Russian Anti-Terrorism Committee has not said what it thought was behind the blast, though Moscow-backed authorities in Crimea have alluded to Ukrainian sabotage.

The cause of the blast is unconfirmed. Some have claimed that it was a car bomb, while others say it could have been an attack from below.

CCTV footage shared online shows a white truck driving along the bridge and then a large explosion.

Oil tankers on the rail section of the bridge caught on fire after the blast.

Ukraine’s security services, the SBU, published verses by the Ukrainian poet about “the Sun which rises on the burning bridge” on Telegram Saturday morning.

“Today is a perfect opportunity to revise some poems by Taras Shevchenko,” they wrote.

Ukraine’s postal service announced it is preparing to print stamps bearing the image of the “Crimean bridge, or, more precisely, what is left of it.”

Russia responded fiercely to comments by Ukraine, claiming they showed its “terrorist nature”.

“The Kiev regime’s reaction to the damage to civilian infrastructure demonstrates its terrorist nature,” Russian foreign affairs spokeswoman Maria Zakharova was quoted as saying by Russian news agencies.

Video footage shared hours after the incident showed that the blazes had been put out, leaving the bridge scorched and partially in the sea.

Russia said it had “opened a criminal investigation in connection with the incident on the Crimean Bridge” on Saturday morning.

Vladimir Konstantinov, head of the Russian-backed Crimean assembly, denounced “Ukrainian vandals” and vowed to reopen the bridge.

No Ukrainian official has claimed responsibility for the blast, happening just one day after Putin’s birthday.

The crossing is a pair of road and rail bridges that Russia built after it seized and annexed Crimea from Ukraine in violation of international law in 2014.

The bridge, completed in 2018, was built at great expense on the orders of Putin and has become symbolic of Russia’s annexation of the peninsula.

Military equipment for the Russian army fighting in Ukraine is transported along the bridge, spanning the Kerch Strait.

Russia has maintained that fighting in Ukraine posed no risk to the bridge, though it threatened Kiev with reprisals if Ukrainian forces attacked Crimean infrastructure.

The bridge’s arches sustained no damage according to an aide to the head of Crimea, Oleg Kryuchkov.

“Arches were not damaged,” he said. “It is too early to speak about causes and consequences.”

In 2019, Putin inaugurated the huge railway bridge — the longest in Europe — saying it “proved” Russia’s ability to carry out large-scale projects.

He said that 14 million passengers and about 13 million tons of cargo were expected to move across the bridge the following year.

Several explosions have torn through Russian military installations on the peninsula in recent months.

The Djankoi military base was devastated in August by a blast at an ammunition depot, which Russia eventually recognized as “sabotage”. — Euronews