Uganda, Feb. 4 -- Missiles are fired on Ukraine's second city from across the Russian border which is so close by that there are only seconds to stop them.

If they're aimed at Kharkiv there's every chance they'll hit - and little chance of reaching shelter.

School and kindergarten buildings have been closed for almost two years for safety, and playgrounds stand empty.

Now, as the full-scale war heads towards its third year, parts of life in Kharkiv are moving underground.

Deep down in the metro, specially built classrooms run parallel to the platform at five stations.

The local authorities began offering school lessons beneath the city streets several months ago.

They've just added preschool classes on the weekends.

Nika's story

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