On Ukraine’s frozen battlefield, government forces and separatists are fighting once again.

In the town of Avdiivka, they’ve had no electricity and hardly any heating for days. Soviet-era rockets are killing civilians.

With the U.S. backing Ukraine’s government and Russia supporting the separatists, the war has claimed nearly 10,000 lives since it began in 2014. Both sides blame each other for the latest upsurge in violence.

CBS Evening News

Ukraine is trying to present itself as a victim of aggression, said Russian President Vladimir Putin today -- accusing the Ukrainian government of attempting to squeeze money out of the U.S. and Europe.

But the latest violence could also be Russia testing the new administration in Washington, and an American president who says he wants a better relationship with Moscow.

The conflict started when protestors ousted President Viktor Yanukovych, who had close ties with Moscow -- and Russia sent in troops to seize the Crimean Peninsula. We watched as eastern Ukraine lurched into chaos.

Three years later, Ukrainians are still dying -- fighting over whether their future lies with Russia or the West.

Senator John McCain urged President Trump in a letter today to arm Ukrainian government forces, saying that Russia is testing the president and is trying to destabilize and dismember Ukraine.