"According to preliminary data, children received shrapnel injuries... and one woman was also injured," in Kharkiv, said Sergiy Bolvinov, head of the Kharkiv region's investigative department.

"As a result of the morning shelling, we have a complete destruction of a section of an apartment building. Now the rescuers are trying to dismantle the rubble in order to find people under it," Kharkiv's mayor said.

Separately, authorities in Kyiv said at least two people were injured in shelling.

"So far, one victim has been hospitalised by medics in Solomyanskyi district", said Kyiv Mayor Vitali Klitschko.