From the New York Times, I'm Sabrina Tavernisi. This is the Daily.

On Monday night, Russian troops crossed into two key regions in eastern Ukraine,

controlled by forces, friendly to Russia, in a possible precursor to a wider war.

This is Lindsay Adario in the village of Novel, Ohansk, we're being sheltered.

We're logging the face down.

The day before, I landed in Kiev, the country's capital, and joined my colleagues

who've been reporting from the ground.

A train is expected to depart full with refugees fleeing one.

They've been in the east, sending dispatches about rising tensions there.

It does feel like from the Russian side a kind of case for going towards being established,

even though the public at large here I think is really just not prepared for this kind of war.

Today, I spoke to one of those colleagues, Valerie Hopkins, about what led to this moment,

and what's coming next.

It's Tuesday, February 22nd.

I arrived in Kiev on Sunday, and it's turned out to be a very significant weekend in the conflict between Russia and Ukraine.

Walk me through where this most recent escalation began. Where did it start?

It all starts in this region of eastern Ukraine called Dumbass, where pro-Masco forces have been in charge since March 2014.

They violently took control of the government and set about trying to create their own statelet.

I remember that fighting really well because I covered that war pretty extensively in 2014.

It was really violent at first, but then it just settled into this slow grinding rhythm.

Exactly. After that, the fighters on both sides dug into their positions.

Sometimes they lobbed mortars back and forth. People did die, but it was really slow burning.

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