A large blast rocked a street in the Russian city of Belgorod, which lies just across the border from Ukraine, late on Thursday but there were no initial reports of injuries, local authorities said.
Belgorod region governor Vyacheslav Gladkov, announcing a state of emergency, said on Telegram that there was a crater measuring 20 meters across (65 feet) on one of the main streets in the city. He did not say what the cause was.
Video footage from the site showed piles of concrete on the street, several damaged cars and a building with broken windows. One shot showed what appeared to be car upside down on the roof of a store.
Belgorod is one of several southern Russian regions where targets such as fuel and ammunition stores have been rocked by explosions since the start of what Moscow calls its "special military operation" in Ukraine on February 24, 2022.