Kiev, Oct 8 (TIWN) The Kerch bridge from Russia to Crimea, a hated symbol of the Kremlins occupation of the southern Ukrainian peninsula, was hit by a massive explosion on Saturday on the span that carries railway traffic.

Images from the bridge showed a fiercely burning fire engulfing at least two railway carriages from a train on the bridge, accompanied by a vast column of black smoke, The Guardian reported.

The explosion, which witnesses said could be heard kilometres away, took place at around 6 a.m. on Saturday morning while a train was crossing the bridge, although it was not immediately clear what caused it.

Some images appeared to show a second fire at some distance from the main blaze.

Later images also appeared to show part of road bridge that runs parallel with the train tracks had collapsed, The Guardian reported.

The bridge is both highly symbolic to Russia and an important logistical supply route for Russian forces in Crimea and in southern Russian-occupied Ukraine.

The Russian news service TASS said a fuel tanker was involved.

"According to preliminary data, a fuel tank (railroad) car has been on fire at one of the sections of the Crimean bridge, shipping arches aren't damaged, said Oleg Kryuchkov, an adviser to the Russian occupation head of the Crimea.

Another Moscow-appointed official said: "A cistern carriage is burning with fuel on one of the bridge sections. Shipping arches aren't affected. Too early to talk about reasons and consequences. Work is under way to put out the fire."