STORY: A blast rocked the Kerch bridge which links Russia and the Crimea peninsula on Saturday (October 8), causing parts of the road to collapse.
The bridge is a crucial military supply route for Russian forces in Ukraine.
Fire and thick smoke were seen on the strategic road-and-rail bridge, which is the only crossing between Crimea and Russia.
Video obtained by Reuters showed CCTV footage of the blast.
Reuters was not able to confirm the date the video was filmed.
It was not yet clear if the blast was a deliberate attack or an accident but the damage to such high-profile infrastructure came at a time when Russia has suffered several battlefield defeats.
And it could further cloud the Kremlin's messages of reassurance to the wider Russian public that the conflict is going to plan.
The Russian Investigative Committee said the blast occurred in a freight truck, causing fuel tanker wagons to catch fire on a train heading for the peninsula.
It added that two sections of the bridge had partially collapsed.
Sergei Aksyonov, the Russian governor of Crimea, said on social media that the road bridge was still intact in one direction.
Although he said traffic was suspended while the damage was being assessed.
In Kyiv, the mood was upbeat.
No one knows how it happened, this man said. But added that everyone had waited for it.
“We have waited for the moment when the bridge burns. I think all Ukrainians waited for it. And we are very satisfied it has finally started.”
A Ukrainian presidential adviser posted a message on Twitter saying the incident was just "the beginning”.
But he stopped short of saying Ukrainian forces were responsible for the blast.
Russia seized Crimea from Ukraine in 2014.
The 12 mile bridge which links it to Russia’s transport network was opened with great fanfare by President Vladimir Putin four years later.
It now represents a crucial supply route for Russian forces who have taken control of most of southern Ukraine’s Kherson region.