Ukraine: Common history pulls in aid from west Russia
The town of Shakhty is less than an hour's drive from Russia's border with Ukraine.
The name means "mines" - a reference to the coalmines that once employed so many, but have now shut.
On the edge of town is a tiny, crumbling Soviet-era museum about the history of the coal industry and the glorious miners of the River Don.
Today, the museum has been turned into an aid centre. Inside there are volunteers packing clothes, food and medicines for people fleeing the conflict in eastern Ukraine.
Local Cossacks are co-ordinating the relief effort.
A deputy Cossack commander called Andrei draws my attention to an old map of Rostov region and eastern Ukraine up on the wall. It dates back more than a century.
"This all used to be our land, the land of the Don Cossacks," Andrei tells me, pointing to Ukraine's Luhansk region. "This is our common history, it's our people. That's why we're helping."
It's not just the Cossacks who've been remembering the past.
Russian politicians - including the president - have been publicly stating that what is now south-east Ukraine was, under the Tsars, a Russian region called Novorossiya.
It helps explain why some Russians have been providing more than just humanitarian aid to those across the border.
About 80km (50 miles) from Shakhty, in the Russian city of Rostov, I talk to Yuri.
A long green mask and dark glasses hide his face. He's agreed to this midnight meeting to tell me about his group's activities.
Via the internet, Yuri has been recruiting Russians to fight in Ukraine on the side of separatist rebels. He says it's to protect the people of Novorossiya.
On its website, the group recently advertised for tank drivers, helicopter pilots and for people who know how to operate rocket launchers.
Kiev has identified this organisation and its website as one of the main recruiting grounds for Russian fighters in Ukraine.
"There is a saying," Yuri tells me. "You can't do good without using your fists. Sometimes it's necessary to take up arms to protect those who need defending. We call it 'armed charity'."
'Nothing to lose'
The group says it was their volunteers who led the attack on Donetsk airport last month.
During the fierce battle, the insurgents suffered heavy losses. Later more than 30 bodies were repatriated to Russia.
"Different categories of people become volunteers," Yuri explains.
"They can be young people or much older. During the battle for Donetsk airport, one of the volunteers was 56 years old. He showed everyone how it should be done. The country can be proud of people like this.
"Some of the volunteers are quite well off, they've giving up the good life to do this. Others have nothing to lose."
Yuri denies that the Russian government backs the volunteers, or that they receive weapons from the Russian army.
How, then, does he explain reports of separatist fighters riding Russian tanks?
"Russian tanks are like Kalashnikov rifles, you can find them all over the place even as far away as Thailand," Yuri says. "They're very popular for armed conflicts. Yes, they're made in Russia. But who knows how they got there?"
Moscow has repeatedly denied sending troops or military hardware across the border.
But Western governments maintain that among the fighters in eastern Ukraine are professionals funded, equipped and supported by Moscow.
What's more, in recent days Nato and Washington have accused Moscow of massing troops on the border.
"Unfortunately, there is mounting evidence that shows a build-up of Russian military forces near the border with Ukraine," White House spokesman Josh Earnest said on Friday.
"Contrary to the statements by Kremlin officials we do not see any evidence that the Russian military units arriving to the region are connected to any type of border security mission…. We will not accept any use of Russian military forces under any pretext in eastern Ukraine."
It's not only Russian volunteers who have taken up arms.
At a hostel near Rostov I meet a group of Ukrainian citizens, who've fled the violence.
Most of the people here claim to have male family members who've stayed behind in eastern Ukraine to become militants. They blame Ukrainian government forces for the deaths of civilians.
Robert tells me about his son who has become a rebel in their home town of Luhansk.
"I hope my son kills 2,000 of those Kiev bandits," Robert says. "If he does, I'll build a statue to him. He'll be my hero."
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