(The Hill) — An explosion Saturday caused the partial collapse of Kerch Bridge, which connects Russia to the Crimean Peninsula, an apparent attack that struck both Russia’s supply lines and a symbol of Russian power in the area. 

According to reports and videos of the incident, a truck blew up and ignited fuel tanks on a passing train, cutting off part of the lone bridge passage to Crimea, which Russia annexed from Ukraine in 2014.

The incident comes after Russia made an escalatory move to annex four occupied regions of Ukraine.

Russian President Vladimir Putin has accused Ukraine in the bridge explosion, which he called a “a terrorist act,” and is expected to meet with his Security Council Monday. Ukraine has not assumed responsibility.

Here are some of the reasons why the Kerch Bridge explosion is significant in the wider war.

It’s personal for Putin 

The Kerch Bridge incident may affect Russian President Vladimir Putin personally, England’s Ministry of Defense said in an intelligence update Sunday. 

“This incident will likely touch President Putin closely; it came hours after his 70^th birthday, he personally sponsored and opened the bridge and its construction contractor was his childhood friend,” the update cautioned. 

The bridge is viewed as the Russian leader’s major, concrete manifestation of his stated claims to retake Ukraine. Russia invaded and occupied Crimea in 2014.

Putin celebrated the opening of the nearly $4 billion bridge in 2018 by driving a dump truck across the span as international powers condemned its construction as violation of international law and rejected Russia’s claims to Crimea. 

Russian logistics ‘crippled’

The explosion also dealt a blow to Russia’s war effort, cutting off a crucial avenue for Russian troops and supplies as fighting continues in Ukraine.  

The incident halted train and automobile traffic and has reduced the transit potential of the 12-mile bridge, which bypasses the Kerch Strait.

The bridge is Russia’s most important link to neighboring Ukraine, as the entryways through other recently annexed areas are less established and more difficult to access.

Timothy Snyder, Yale historian of Russia and Ukraine, tweeted on Saturday that the bridge explosion “cripples Russian logistics and dissolves the major symbol of Putin’s power.”

A bridge engineer told the Wall Street Journal that it would take several months to restore damaged sections of the bridge.

Ukraine celebrated the blast

While Kyiv hasn’t claimed responsibility for the explosion, some Ukrainian officials celebrated the incident.

The official Twitter account for Ukraine’s government posted Saturday night, sharing just the English phrase “sick burn.”

While many Russians view the Kerch Bridge as a symbol of Moscow’s influence in the area, many Ukrainians see the bridge as representative of Russian occupation.

“The guided missile cruiser Moskva and the Kerch Bridge – two notorious symbols of russian power in Ukrainian Crimea – have gone down. What’s next in line, russkies?” Ukraine’s Defense Ministry tweeted Saturday, referencing the bridge collapse and damage earlier this year to an important Russian warship.

Ukrainian President Volodymy Zelenskyy responded to the explosion in his address Saturday night, saying the future for Ukraine is “sunny.”

“This is a future without occupiers. Throughout our territory, in particular in the Crimea,” he said.

Heightens nuclear fears 

Former Joint Chiefs of Staff Chairman Mike Mullen cited the bridge explosion Sunday as the latest setback for Russia that raises the potential threats of a nuclear attack.

Putin has also put the international community on high alert with his recent rhetoric about nuclear weapons. 

“He’s a cornered … animal and I think he’s [become] more and more dangerous,” Mullen said. “I think we have to take him seriously and think through what the requirements would be to respond to that. It also speaks to the need to get to the table.”

Following a string of Ukraine gains last month, Putin delivered a high-profile speech mobilizing hundreds of thousands of military reservists and warning, “We will certainly use all means available to us” to defend Russia, adding, “This is not a bluff.”

A number of U.S. officials, including President Joe Biden, have expressed grave concerns over Putin’s single-handed power over the weapons’ possible deployment, though they have said there are no signs of an imminent attack.

Russia’s deadly response

In the wake of the Kerch Bridge explosion, Ukrainian officials announced Sunday that Russian overnight strikes killed at least 17 in Zaporizhzhia, a Ukrainian city claimed by Moscow in the recent annexations.  

Zelenskyy called the strikes “merciless” in a post to his Facebook page.

“Absolute meanness. Absolute evil. Savages and terrorists. From the one who gave this order to everyone who fulfilled this order. They will bear responsibility. For sure. Before the law and before people,” he wrote.

Anatoliy Kurtev, secretary of Zaporizhzhia’s city council, wrote on Telegram that 40 people were injured by the blasts, which he said also damaged 50 high-rise buildings, four educational institutions and 20 other private-sector buildings. 

Outside of the city lies Europe’s largest nuclear power plant, which Russian military forces have occupied since early in the war.

Zelenskyy has long condemned Russia’s “nuclear terror” and “nuclear blackmail” at Zaporizhzhia, and warned last week that Russian leaders are beginning to “prepare their society” for the weapons’ use.