Dozens of people have been killed in clashes between Azerbaijan and Armenia in the disputed Caucasus region of Nagorno-Karabakh.

Armenia said 18 ethnic-Armenian soldiers had died in the fighting, among the worst in two decades.

Azerbaijan said it had lost 12 troops and there were unconfirmed reports of civilian deaths on both sides.

Nagorno-Karabakh has been in the hands of ethnic-Armenian separatists since a war that ended in 1994.