Ukraine crisis: On the front lines with a rebel dog

The front lines in eastern Ukraine changed significantly today.We saw it happen.

We headed out earlyto a church servicenear the Malaysia Airlines Flight MH17disaster site,taking the same route we had for days,passing sunflower fields still dotted with wreckage.

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Suddenly, rounding a corner, we saw two cars of rebel fighters. They jumped out, dived in the ditches and dropped to their bellies near a train track.

They waved us on urgentlydown the road.Somethingwas brewing.

At the next intersection, there were more rebels.We were told Ukrainian tanks were up ahead. They said, "Go if you like, but youmight get caught between the Ukrainian army and us."Not a good idea.

We turned around, but before we could leave, one of the fighters rushed up,pleading with us,"Take my dog at least hewont die."

And then he shoved a black dog into our van.

"Drop it at the next safest town,"he told us,closing the door and running back into position.

We carried on, passing through villages taut with nervousness. There was shelling in the city ofTorez, where a train carrying the bodies of flightMH17 was loaded a week ago.

We gave the rebel dog some water and let it out in one of the towns.

At the crest of a hill in another,we stopped to survey the scene.We were about five kilometres from where the cockpit of flight MH17 had plunged into a sunflower field.

Suddenly behind us we heard the sounds of a convoy.Ukrainian armoured vehicles,waving the blue and yellow flag about 20 of them artillery, anti-aircraftand armoured personnel carriers,rolling by us.

Yesterday this area was controlled by pro-Russian separatists.They headed down the hill into the valley,advancing against the rebels.

The heightened tension cancelled a planned visit to the crash site by an international observer team, along with Dutch and Australian aviation and forensic experts.