Russian air defense systems destroyed a Ukraine-launched unmanned aerial vehicle over the Belgorod region early on Sunday morning, the Russian defense ministry said.
Ukraine launched missile and drone attacks on the Russian border district and Crimean bridge as Kyiv started registering ships willing to use the Black Sea corridor on Saturday.
The latest attack was intercepted by missile defenses as a drone from Ukrainian troops was shot down above the Belgorod region on Sunday morning, Russia's Defense Ministry said.
Three Ukrainian missiles were shot down over the Kerch Bridge that connects Crimea to the Russian mainland, said Crimean governor Sergey Aksyonov.
"Two enemy missiles were shot down by air defense forces near the Kerch Strait. The Crimea bridge has not been damaged," Aksyonov said.
Shortly after, Aksyonov updated on his Telegram channel that another missile had been shot down in the Kerch Strait in the Black Sea on Saturday.
The bridge, a vital link for Russia's special military operation in eastern Ukraine, has come under repeated attacks during the conflict.
Russia's Defense Ministry said the Ukrainian troops attempted to hit the bridge with surface-to-air S-200 missiles on Saturday afternoon, and 20 drones were shot down on their way to the peninsula on Sunday morning.
Russian Foreign Ministry spokeswoman Maria Zakharova said Ukraine's "act of sabotage" will be responded to in kind. "There can be no justification for such barbaric actions and they will not go unanswered," she wrote in a post on Telegram.
Interfax news agency reported the bridge had been briefly shut for traffic but that it had later reopened.
Ukraine opened registration on Saturday for merchant ships sailing through temporary corridors in the Black Sea, according to the Ukrainian Navy.
"Registration is now open, and the coordinator is already working," a spokesperson from the Ukrainian Navy, Dmytro Pletenchuk, said on national television.
The temporary routes aim to overcome the global food security crisis, Pletenchuk said, adding it would allow shipowners and companies to "finally take back their merchant vessels that are in humanitarian captivity due to the constant threats of Russians at sea".
The Ukrainian Navy first announced the temporary corridors for civilian ships to sail to and from Ukrainian ports in the Black Sea on Thursday. The navy said only vessels whose owners or captains officially accept the current conditions will be allowed to use the routes. However, it is not immediately clear when ships will begin using the new routes.
Several beaches in the Black Sea city of Odesa were officially opened for swimming for the first time since the start of the conflict.
Until now the local authorities had banned swimming due to the risk of mines in the sea washing up near bathers. The Governor of Odesa, Oleh Kiper, said the decision to open the beaches had been made jointly by the city's civilian and military administrations.
The beaches would be open from 8 am to 8 pm but would close when air raid sirens are sounded, he said. Nets have been set up to catch sea mines that might otherwise end up close to the shore.