Ukraine's defence ministry said on Monday that an explosion in Dzhankoi in the north of the Crimean peninsula destroyed Russian cruise missiles intended for use by Russia's Black Sea fleet.
A Russia-installed official in the peninsula, which was annexed by Moscow in 2014, said the blast was caused by drones laced with shrapnel and explosives and targeted civilian sites. One person was injured.
A statement by the intelligence directorate of Ukraine's Defence Ministry said: "An explosion in Dzhankoi city in the north of temporarily occupied Crimea destroyed Russian Kalibr-KN cruise missiles as they were being transported by rail".
The statement on social media said the missiles, designed to be launched from surface ships in Russia's Black Sea fleet, had an operational range of more than 2,500 km on land and 375 km at sea.
Ihor Ivin, the Russian-installed head of the Dzhankoi administration, was quoted as saying the city had come under attack from drones and a 33-year-old man suffered a shrapnel injury from a downed drone. He was taken to hospital and expected to survive.
Reuters was not able to independently verify neither the Ukrainian nor the Russian reports.
TASS quoted Ivin as saying on Krym-24 TV that a house, school and grocery store caught fire, and the power grid sustained damage.
Oleg Kryuchkov, an adviser to the Russia-installed head of Crimea, said the drone attack was aimed at civilian targets.
"All the drones targeted civilian sites. One was hit over the Dzhankoi technical school and came down between the instruction area and a student residence," he said on his Telegram channel.
"There are no military sites nearby. The others were downed in residential areas. In addition to explosives, each one carried shrapnel."
A Russian military air base is located near Dzhankoi, with Ukrainian officials long saying that the city and the surrounding areas have been turned into the largest Moscow military base in Crimea.
Ukraine has staged a number of daring attacks on targets in Crimea. Last August, missiles destroyed several planes at an air base on the peninsula's south west coast and Ukrainian authorities later claimed responsibility for the attack.