https://www.bbc.com/news/world-europe-61607184
And some who have been pulled off the front lines are refusing to go back.
""...I had thought that we were the Russian army, the most super-duper in the world," says the young man bitterly. Instead they were expected to operate without even basic equipment, such as night vision devices, he says.
"We were like blind kittens. I'm shocked by our army. It wouldn't cost much to equip us. Why wasn't it done?"
Sergey joined the army as a conscript - most Russian men between the ages of 18-27 must complete one year of compulsory military service. But, after a few months, he made the decision to sign a two-year professional contract which would also give him a salary.
In January, Sergey was sent near the border with Ukraine for what he was told would be military drills. A month later - 24 February, the day Russia launched its invasion - he was told to cross the border. Almost immediately his unit found itself under attack.
As they stopped for the evening in an abandoned farm, their commander said: "Well, as you will have worked out by now, this is not a joke."
Sergey says he was completely shocked.
"My first thoughts were 'Is this really happening to me?'"
They were continually shelled, he says, both when moving and when parked overnight. In his unit of 50 people, 10 were killed and 10 others wounded. Almost all his comrades were under the age of 25.
He heard of Russian servicemen so inexperienced that they "did not know how to shoot and couldn't tell one end of a mortar from another".
He says his convoy - travelling through northern Ukraine - broke up after just four days when a bridge they were about to cross exploded, killing comrades ahead of them...."