Traffic has been halted on the Russian-built Crimean bridge due to “an emergency” – thought to be an attack by Ukraine – early on Monday.

Russia-installed officials said confirmed the predawn attack, while Ukrainian media reported blasts on the Kerch Bridge.

Russia’s Grey Zone channel, a Telegram channel affiliated with the Wagner mercenary group, reported two strikes on the bridge shortly after 3am (local time).

Sergei Aksyonov, a Russian-installed governor, told Reuters there had been an “extraordinary event” at the 145th pillar of the bridge, the only link between Russia and the annexed Ukraine territory of Crimea.

“Law enforcement agencies and relevant services are at work. I spoke to the Minister of Transport of the Russian Federation Vitaly Savelyev, and measures are being taken to ameliorate the situation,” he said.

“Given the current situation, I ask residents and guests of the peninsula to refrain from traveling through the Crimean bridge and, for security reasons, choose an alternative land route through new regions.”

Russia’s transport ministry said that there was damage to the road on the bridge closer to the Crimean Peninsula, but there was no damage to the pillars. It did not say what the cause was.

There are widespread reports on social media of at least two missile strikes, and that at least one span of the 19-kilometre road and rail bridge has collapsed.

The governor of Russia’s Belgorod region, Vyacheslav Gladkov, said two people had died and their daughter was injured when the bridge was hit they were driving across it. The young girl suffered “moderate” injuries and was being treated by doctors, he said.

Serhiy Bratchuk, spokesperson for Ukraine’s Odesa military administration, posted a photo on his Telegram of what seemed to show the line of the bridge in distance, broken in the middle.

Tweet from @Tendar

It was not immediately clear whether that was related to the attack.

The bridge is a critical artery for supplying Crimea with goods, as well as supplies for the military.

The Russian-backed administration of the peninsula said Crimea had all necessary stock, but urged residents not to travel via the Kerch Bridge.

Mr Akysyonov said the deputy chairman of the Council of Ministers of the Republic of Crimea, Igor Mikhailichenko, was on the scene.

The bridge was also damaged in an explosion last October, causing a partial collapse. The Kremlin immediately blamed Ukrainian security forces. Kyiv reacted with glee, but did not initially admit to the attack.

Russia made hasty repairs after the 2022 attack, and the vital supply route was back in operation by February.

Tweet from @KyivPost

Russia spent about $US3.7 billion ($5.4 billion) building the Kerch Bridge after its illegal annexation of the Crimean Peninsula in 2014. It was the physical expression of President Vladimir Putin’s objective to take over Ukraine and bind it to Russia forever.

George Barros, an analyst at Washington’s Institute for the Study of War, said on Twitter that if the bridge was seriously damaged it would significantly impact Russian supply lines.

“Russia will only have one ground supply line – the coastal highway on the Sea of Azov – to sustain (or evacuate) its tens of thousands of troops in occupied Kherson & Crimea if UKR manages to degrade/destroy the bridge,” he said.

It was not immediately clear what Monday’s incident will mean for the UN-brokered deal that allows the safe Black Sea export of Ukrainian grain. It expires later on Monday, and was still uncertain late on Sunday (local time).

The Crimean peninsula has been a major and cherished holiday destination for Russians, especially after Moscow launched its invasion on Ukraine in 2022 and travelling to the West became more difficult for many Russians.

In recent weeks, there have been kilometres-long traffic jams to the entrance of the bridge every day as Russians head off on holidays.

Traffic was backed up again on Monday morning before police directed vehicles away from the bridge. Social media accounts showed cars lined up on the bridge and its entrance.

-with AAP