In the eastern Ukrainian city of Kramatorsk, near Slaviansk, the gutted remains of busses and cars used as barricades smolder.

A testament to the latest clashes between government forces and pro-Russian separatists in the east.

(SOUNDBITE) (Russian) KRAMATORSK RESIDENT, ILYA, SAYING:

"A checkpoint from Slaviansk was under fire, there were a lot of victims from both sides, from the civilians and from the fighters at the checkpoint. People who were simply going to work were injured."

It's the second day of a government military operation to oust armed rebels from their strongholds.

The government says there was heavy fighting in Kramatorsk.

A security chief offers few details but says the military operation to take back the east is complex.

(SOUNDBITE) (Russian) DEPUTY CHIEF OF SBU AND CHIEF OF THE ANTI-TERRORIST CENTER, VASYL KRUTOV, SAYING:

"What we are facing in the Donetsk region and in the eastern regions is not just some kind of short