KYIV (Reuters) - Ukraine's SBU security service and navy struck the Saky air base in Russian-occupied Crimea overnight, inflicting "serious damage", a Ukrainian intelligence source said on Thursday.
The Russian military, meanwhile, said it had destroyed 19 Ukrainian drones over Crimea and the Black Sea, and gave no details on casualties or damage.
Reuters could not independently verify the reports.
"Strikes by the Security Service and the Navy hit the target and caused serious damage to the occupiers' equipment," the source said, describing an operation that the source said used first drones and then Neptune cruise missiles.
The source said that at least 12 combat aircraft and man-portable air-defense system were located at the base in western Crimea and that the base was also used as a training base for drone operators.
Ukraine has ramped up attacks in the Black Sea and Crimea, which was seized and annexed by Russia in 2014, as Ukrainian forces press on with a nearly four-month-old counteroffensive.
Kyiv said a series of attacks on Crimea last week damaged two Russian patrol ships and destroyed a sophisticated air defence system.
On Wednesday Kyiv said Ukrainian forces struck a Russian Black Sea fleet command post near Sevastopol in Crimea.
(Reporting by Tom Balmforth; writing by Anna Pruchnicka; ediitng by Mark Heinrich and Timothy Heritage)