New fighting between Armenians and Azerbaijanis

(Vatican Radio)-- Officials say at least 15 soldiers have been killed in the worst clashes in years over the disputed Armenian enclave of Nagorno-Karabakh in Azerbaijan. The sharp escalation in fighting between Armenian troops and Azerbaijan's army for the territory prompted Russia to issue an urgent call for calm.

Azerbaijan's Defense Ministry says at least a dozen of its troops were killed in recent days, including four over the weekend as battles rage around Nagorno Karabakh.  

Click below to hear the report fromcorrespondent  Stefan Bos

Local authorities in Nagorno-Karabakh said at least three of their soldiers were killed this week, "including one on Saturday". 

Azerbaijan's Nagorno-Karabakh region and some adjacent territory have been under control of Armenia's army and local ethnic Armenian forces since the end of a six-year separatist war in 1994.

Both sides report frequent shootings and attempted incursions along the cease-fire line, but the latest outbreak of fighting has been the worst in years. 

REASON UNCLEAR

Observers said it was not immediately clear what sparked the latest clashes between the former Soviet republics Azerbaijan and Armenia, as they accuse each other of being the aggressor. 

Russia's Foreign Ministry expressed concerned about the fighting and the deaths it caused, saying "further escalation is unacceptable" and urging all sides to end the fighting.  

However critics claim Russia's annexation of Ukraine's Crimean Peninsula contributed to tensions. 

Armenia, which depends on Russia for economic and military support, has welcomed the recent takeover of Crimea, with some Armenians suggesting it could be a model for Nagorno-Karabakh.  

These sentiments have angered Azerbaijan, which like Ukraine has aligned itself with the West.