The baby-faced teenager in baggy shorts raced his skateboard past the bombed burger joint and hit Peace Square just as air raid sirens rolled over the Ukrainian front.

He crashed a few times doing flips on the vast and entirely deserted expanse at the heart of Ukraine's administrative centre for the eastern war zone.

White vapour trails streaking across the evening sky bore testament to the multiple rocket launcher systems firing their salvos around Kramatorsk -- a city whose seizure would prove momentous for the Russians in the third month of war.

But Roman Kovalenko felt an odd mixture of invincibility and disbelief with the skateboard under his sneakers.

The main square in Kramatorsk was once teaming at sunset with skateboarders such as Roman Kovalenko
The main square in Kramatorsk was once teaming at sunset with skateboarders such as Roman Kovalenko AFP / Yasuyoshi CHIBA

"On the one hand it's sad, but on the other, it's a special atmosphere," the 18-year-old said of the air raid sirens and the sleepless nights spent by many who have still not fled for safety to the west of Ukraine.

At least five powerful long-range missiles had smashed into Kramatorsk before sunrise that day.

The walls and ground across the city shook and rows of residential buildings -- now standing largely abandoned -- had their windows blown and apartments turned inside out.

As he rolled alone into the sunset in his white baseball cap, Kovalenko cut a picture of an ordinary kid dropped in the middle of a war that few could have imagined in the 21st century.

The missile strikes and encroaching fighting have forced the vast majority of Kramatorsk's residents to flee
The missile strikes and encroaching fighting have forced the vast majority of Kramatorsk's residents to flee AFP / Yasuyoshi CHIBA

"I feel a sort of melancholy because there is no one around," he said.

"But walking alone before military curfew, I feel like the king of the streets."

The industrial city of Kramatorsk had 300,000 people before a years-long east Ukrainian insurgency exploded into the gravest European conflict since World War II.

Kramatorsk has been hit by waves of long-range missile strikes that have torn up apartment blocks and kept residents awake at night
Kramatorsk has been hit by waves of long-range missile strikes that have torn up apartment blocks and kept residents awake at night AFP / Yasuyoshi CHIBA

The rebels' capture of the Donbas region's capital Donetsk in 2014 forced the pro-Western leaders in Kyiv to move their administrative centre about 80 kilometres (50 miles) to the north in Kramatorsk.

The Soviet-era city -- much of its architecture identical to similar working-class towns across Russia -- is dominated by a row of factories running along a railway line in a riverside valley.

These sprawling warehouses and plants make perfect targets for Russian forces that are slowly creeping up to Kramatorsk from across the rolling hills to the north.

Weeks of trench warfare involving increasingly powerful weapons has enabled the Russians to encroach within striking distance by their heavy tanks and other big guns.

A giant national flag overlooking Kramatorsk has been lowered in mourning for the victims of the missile strikes
A giant national flag overlooking Kramatorsk has been lowered in mourning for the victims of the missile strikes AFP / Yasuyoshi CHIBA

The Ukrainians counterattack with shellfire in the morning.

They then try to move their equipment around in the daytime to make sure the Russians do not have clear targets to hit with long-range missiles at night.

This routine has been grinding on with frightening predictability for days.

Kovalenko has been witnessing the ruin this has wrought on his city while trundling around its deserted streets on his sticker-marked skateboard.

"I have nothing else to do," he shrugged. "All my friends have moved out to different parts of Ukraine. And I'm bored."

Peace Square in the city centre used to be a favourite haunt for skateboarders and other teens looking for a free evening out.

The sunset over the river turns the drab government buildings gold and adds a jarring charm to a city whose main inhabitants are now muscle-bound men with assault rifles and weary expressions on their grizzled faces.

Kovalenko has trouble explaining why he is still here among these warriors and not out west with his friends.

"Of course I would like to meet up with my friends and go out, but that's not really possible now," he said.

Family turmoil has left him living alone with his mother. He hints at financial problems but quickly adds that other people have much bigger problems.

"The time hasn't come yet for me to be afraid," he said. "I am a fatalist by nature. I accept my fate."

A new round of air raid siren wails erupts from speakers directly overhead.

He ignores them.

"When a siren sounds, 80 percent of the time, nothing happens," he said.

He then paused and amiably conceded that one out of five rockets striking their targets was still not terribly good.

"I realise there is a war on, but not completely," he admitted.