By Merlyn Thomas, BBC News
Russia ramped up security on its only bridge to Crimea after a huge blast destroyed sections of it on Saturday.
President Vladimir Putin has now ordered the country's Federal Security Service (FSB) to oversee the key crossing to the occupied peninsula.
The bridge is also a pivotal symbol of Russia's annexation of Crimea from Ukraine in 2014. The blast killed three people, Russian investigators said.
Officials said work to fix the damaged sections would begin immediately.
Russian Deputy Prime Minister Marat Khusnullin ordered the destroyed parts of the bridge to be taken down, and said divers would begin investigating damage below the waterline on Sunday morning.
Video shared on social media showed a long queue of vehicles at the bridge to leave Crimea towards Russia on Sunday.
6km-long queue before the bridge on the way out of Crimea, according to Russian war propaganda project WarGonzo. pic.twitter.com/bO4kASV8Nw
— Leonid ХВ Ragozin (@leonidragozin) October 9, 2022
Hailed by Russian media as "the construction of the century", the bridge has been crucial to Russia for the movement of military equipment, ammunition and troops into southern Ukraine.
New satellite images released on Saturday showed smoke and fire near the collapsed areas of the 19km bridge, which was opened with much fanfare four years after Moscow annexed Crimea.
Since the bridge plays a strategic role in the war, Ukrainian authorities have said it is a legitimate target, as they vow to retake the peninsula.
Ukrainian officials responded with thinly veiled approval to the explosion - but have not indicated that their forces were behind the attack.
President Volodymyr Zelensky acknowledged the incident in his nightly address on Saturday, saying: "Today was not a bad day and mostly sunny on our state's territory."
"Unfortunately, it was cloudy in Crimea. Although it was also warm," he added.
Russian authorities moved swiftly to reopen those parts of the key crossing still intact, and said late on Saturday that the bridge had been partially reopened to road and rail traffic.
Speaking on Sunday, the Moscow-appointed governor of Crimea, Sergei Aksyonov, said rail traffic would continue as normal but the surviving roadway would for now take only light vehicles.
Lorries and buses would be transported by ferry, he added.
The bridge is a vital artery in Moscow's supply chain to the battlefront in its invasion of Ukraine - and to the annexed Crimean territory itself.
President Putin is to hold a meeting of the Russian Security Council on Monday, in what the Kremlin says is a planned event.
Aksyonov said there was a desire for revenge, but made reassurances that the peninsula still had a month's worth of fuel and more than two months' worth of food.
"The situation is manageable - it's unpleasant, but not fatal," he said.
Ukrainian official David Arakhamia, parliamentary head of Zelensky's party, said "Russian illegal construction is starting to fall apart and catch fire.
"The reason is simple: If you build something explosive, then sooner or later it will explode."
And a Ukrainian MP told the BBC that regardless of who was responsible for the attack, this was a "big Ukrainian victory and very severe and hard loss for Russia".
"The bridge is not destroyed but damaged, but the image of Putin is destroyed, that is the most important thing," Oleksiy Goncharenko said.
It is hard to overstate the political, symbolic and strategic significance of the Crimean bridge. Russian officials previously claimed it was well protected from threats from air, land or water - particularly since it is more than 100 miles from Ukrainian-held territory.
A Russian national anti-terrorism committee said the damage was caused by a truck bomb blowing up, which caused seven railway carriages to catch fire. The home of a man from the Krasnodar region of southern Russia is being investigated, it added.
While Ukraine has not linked its armed forces to the explosion, it has targeted Crimea in the past. Last month, Ukraine claimed responsibility for a series of air strikes on Crimea - including an attack on Russia's Saky military base.
Since the bridge attack on Saturday, Ukraine's social media has erupted in celebration. Its second-largest bank says it has already issued a new debit card design featuring the collapsed bridge.
In recent weeks, Kyiv's forces have taken back significant amounts of territory seized by Russia earlier in the war.
Hours after the bridge explosion, Russia appointed a new commander to lead its troops in Ukraine. Sergei Surovikin is a veteran commander known for leading Russian forces in Syria and was accused of overseeing the decimation of the city of Aleppo.
But Russia still controls swathes of Ukraine, including the Zaporizhzhia nuclear plant - the biggest in Europe.
Additional reporting by Patrick Jackson, BBC News
- BBC