Deep in the woods in eastern Ukraine, a tank unit has hidden itself underneath the trees. 

Their giant machines, which include Soviet-era T-72s and a more advanced T-84 are protected by summer foliage in a luxurious stand, the plump leaves blocking out most of the light.

Still, that is not enough to reassure the tank crews who fear the consequences of being spotted by a Russian drone.

Each tank has been draped in camouflage nets and branches, making them virtually invisible to the human eye. We drove past six or so tanks on the way into woods and we did not spot a single vehicle.

I asked the unit’s commander, Lt Vitalii Timoshuk, why they had taken such care to disguise them.

“If we have no equipment, we haven’t anything to fight with. What can I say? We are keeping our tanks safe because we don’t have many of them.”

We found the members of one tank crew, working furiously on a T-84. It is a precious piece of kit, the most advanced tank in the military – although Ukraine only has six of them.

Clutching an oversized spanner, Andrii Koval told us that it is powerful and fast – although sometimes difficult to start.

“There are some questions but in general, it’s a good machine. It shoots well at distances of three to four kilometres and drives fast. That’s all we need.”

Andrii and his colleague, Vadim are on their third tank now. They lost the first two to heavy Russian fire.

A video of the strikes on the first one show its turret smoking in the distance. The crew evacuated and Andrii and Vadim are pictured in the field.

“A direct hit on our vehicle, the crew has evacuated, spotter, mechanic….and me, who is being shot at.”

A Russian shell whizzed over their head.

Combatants using their phones to document the battle as they participate in it has become a feature of this war.

When the commander of this secret tank base, Lt Vitalii Timoshuk, told us how his unit repelled a Russian attack last week, he also had the pictures to illustrate it.

Lt Timoshuk is just a 21-year-old and officially graduated from his military academy on the day of our visit.

But he says he gets plenty of help from his team.

“Our people are experienced, they know why they came here, because of their families and our motherland. This will help us to win.”

“You’re not that experienced, you’re 21 years old and you’re leading the unit,” I suggested.

He replied: “I have no difficulties because my personnel support me. I am proud of them. And it’s my pleasure to command and work with them. Our guys are so cool.”

“What did they think when you arrived, a 21-year-old, leading unit?” I asked.

“I didn’t tell them I was 21 for a long time. I don’t look 21. What else can I say?”

The stolen Russian tank

Lt Timoshuk told me that the Ukrainians have captured some 400 Russian armoured vehicles, including five snagged by his unit.

He introduced me to tank crew member Roman Batsenko, who stole two tanks from under the noses of the enemy.

“Our intelligence told us about them. One had hit a mine. The other one was working so we went (to get them).”

I asked him how he felt the moment he jumped into a Russian tank.

“Happiness, happiness that we renewed our stock of tanks. The only fear came later when we learned there were two hundred Russian tanks just one kilometre away. But they didn’t expect us to be so brazen and steal them.”

The Russian military is formidable and far better equipped but there is plenty of spirit in the woods. The Russians can be defeated, says the unit’s commander, but they’ll have to be smart to get through it.