Satellite images show 40 mile-long Russian military convoy heading for Kyiv | Ukraine invasion latest

Clinging to his mother in the basement of Kyiv’s main children’s hospital, the four-year-old boy ground his teeth, making a scratching sound, writes Sky News’ security and defence editor, Deborah Haynes. 

Nikita Synytsky, who has leukemia and Down’s syndrome, started making the noise when Russia launched its invasion of Ukraine last week, causing his life even more trauma.

“We are very nervous,” said Tatiana Pakhaliuk, his tired-looking mother, holding him tight.

“My son – you see the voice [sound] of teeth, he pushes his teeth,” she said.

Nikita, along with a group of other seriously-ill, infant inpatients, relies on life-saving treatment at the hospital.

It cannot stop even when Russian missiles and bombs started falling.

Instead, each child, typically accompanied by a parent, has had to move to the basement of the multi-storey building, where they are better protected from airstrikes and gunfire.

But it is not only the gravely sick this hospital is trying to help.

Medics set up an emergency department within the first 24 hours of the war to treat children – and adults – in the city who suffer injuries in the fighting.

Three children have so far been brought to the facility – all with gunshot injuries. 

They all appeared separately on the night of Friday into Saturday.

One of the infants, a 10-year-old boy, died en route.