New clashes in eastern Ukraine kill many

(Vatican Radio) Ukraine's central government says Russian-backed separatists have launched a large scale offensive in the east in escalating fighting that killed more than a dozen people. 

Listen to Stefan Bos' report:

Pro-Russian separatists and government forces are now involved in the worst clashes since a shaky European-brokered cease fire was signed in Minsk, Belarus, in February. 

Russian forces can be seen shooting at troops send by Kiev. It's difficult to report with certainty who started this latest battle, which is focused on the village of Maryinka, near the rebel stronghold of Donetsk.

Both sides seem to use heavy artillery, that was supposed to have been withdrawn under a peace deal. But efforts to improve a shaky ceasefire failed this week as talks broke down in Minsk.  

Many Killed

Rebels claim that 15 separatist fighters and civilians have been killed in fresh clashes since Wednesday. Some 60 people are believed to have been injured. Medics on the government side say at least one civilian has died and five more were wounded and officials claim at least seven government troops were injured.

Rebels have denied that they had started a new assault.

But Kiev disagrees. Ukraine's military says rebels have started a new offensive close to the rebel bastion Donetsk involving some dozen tanks and up to 1,000 fighters.

"Tanks, mortars, artillery were used. The enemy is trying to move forward,” said Ukrainian military spokesman Andriy Lysenko. “The Ukrainian servicemen rebut all attacks and successfully hold their positions. The situation is under their control.”

Key City

Further south of Maryinka lies Mariupol, a major Ukrainian port near which fighting has continued despite the ceasefire, ravaging the village of Shyrokyne.

The conflict in eastern Ukraine has killed over 6,400 people since it began in April, 2014 and rights groups have expressed concerns over reported summary executions and the mistreatment of prisoners on both sides.

The Kremlin -- accused by Kiev and the West of orchestrating the conflict -- lashed out at what it called "provocative actions" by the Ukrainian army.

But the US State Department said Russia bears direct responsibility for preventing these attacks and implementing a ceasefire. "Russia bears direct responsibility for preventing these attacks and implementing a ceasefire," added spokeswoman Marie Harf.

And she warned: "Any attempts to seize additional Ukrainian territory will be met with increased cost," an apparent reference to more sanctions.