A Ukrainian attack on a military airfield in Russian-occupied Crimea on Wednesday seriously damaged four missile launchers, three radar stations and other equipment, Ukraine's military spy agency said on Thursday.

Four launchers for S-400 surface-to-air missiles and an air defense control point stationed at an air base in Dzhankoi were among equipment "destroyed or critically damaged", the agency said on Telegram.

It added that the number of aircraft damaged or destroyed as a result of the attack was being clarified.

Several Telegram channels reported powerful blasts in Dzhankoi on Wednesday. Reuters was not able to verify the accounts.

There was no official comment from Russia.

The Ukrainian agency did not provide any data regarding the means used for the strike which it described as "successful". President Volodymyr Zelenskiy earlier thanked military involved in the operation "for precision".

Russian troops have recently stepped up ballistic missiles attacks on Ukraine from Crimea, which Moscow seized and has occupied since 2014. REUTERS