KYIV, May 5 (Reuters) - Russia said on Thursday that its artillery struck multiple Ukrainian positions and strongholds overnight, killing over 600 fighters.

"The armed forces of the Russian Federation continue the special military operation in Ukraine", the defence ministry said. "Over 600 nationalists and 61 units of weapons and military equipment were destroyed".

The defence ministry also said its missiles destroyed aviation equipment at the Kanatovo airfield in Ukraine's central Kirovohrad region and a large ammunition depot in the southern city of Mykolaiv.

Russia sent tens of thousands of troops into Ukraine on Feb. 24 in what it called a special operation to degrade its southern neighbour's military capabilities and root out people it called dangerous nationalists.

Ukrainian forces have mounted stiff resistance and the West has imposed sweeping sanctions on Russia in an effort to force it to withdraw its forces.