The leader of Armenian separatists in Nagorno-Karabakh said on Thursday Azerbaijani forces were closing in on the town of Shusha, whose capture would mark a turning point after a month of fighting.
In a video recorded outside the town's famed cathedral, separatist president Arayik Harutyunyan warned that advancing enemy forces were "five kilometres (three miles) at the most" from the town.
"The enemy's main goal is to capture Shushi... whoever controls Shushi controls Artsakh," he said, using the Armenian names for the town and Nagorno-Karabakh.
He called on Armenians to come to the defence of the strategically important town, the second-largest in Karabakh after the main city Stepanakert.
"In the next few days we need to reverse this situation at the front and punish the enemy right at the gates of Shushi. Let's unite and fight together," he said.
Gaining control of Shusha would be a major victory for Azerbaijani forces, who have been making gains against Armenian separatist fighters since new fighting erupted over Nagorno-Karabakh a month ago.
The town is located on strategic heights over Stepanakert and on the road linking the city with Armenian territory.
Azerbaijan and Armenia have been locked in a bitter conflict over Karabakh since Armenian separatists backed by Yerevan seized control of the mountainous province in a 1990s war that left 30,000 people dead.
Karabakh's self-declared independence has not been recognised internationally, even by Armenia, and it remains a part of Azerbaijan under international law.
The heaviest fighting since a 1994 ceasefire erupted on September 27 and has persisted despite intense diplomatic efforts to bring it to a halt.
The two sides have three times agreed to ceasefires -- the latest in a US-brokered deal at the weekend -- but the truces have all quickly fallen apart.
The fighting has intensified in recent days including with renewed shelling and rocket attacks on civilian areas.
- Heavy missile strikes -
Karabakh's rights ombudsman Artak Beglaryan told AFP earlier on Thursday that Azerbaijan had launched some of its heaviest strikes yet.
"Azerbaijan struck Stepanakert for several hours, tens of missiles hit the city," he said. "Civilians were injured as a result of the strike, the heaviest during the recent fighting."
The strikes came after Azerbaijan accused Armenian forces of killing 21 people and wounding dozens in a missile strike on the town of Barda on Wednesday.
More than 1,200 people from both sides have been reported dead since the fighting began, including over 130 civilians, and thousands forced from their homes.
Azerbaijan has not released any figures on its military casualties and the death toll is believed to be higher, with Russian President Vladimir Putin saying last week that close to 5,000 people had been killed.
Diplomatic efforts have continued, though planned talks involving the two countries' foreign ministers in Geneva on Thursday were postponed for at least a day.
The talks were to be mediated by the Minsk Group of Russia, France and the United States, which have tried since the 1990s to bring about a negotiated settlement to the conflict.
Azerbaijan has claimed to be making significant gains since the fighting began by retaking areas it lost in the 1990s war, in particular in a buffer zone outside Karabakh seized by the Armenians.
Armenia has admitted to suffering losses and called on volunteers to join the fighting.
Azerbaijan said on Thursday it had handed to Armenia the bodies of 30 troops killed in fighting.
"Armenia has failed to show good will in that matter," but thanks to Russian mediation has "agreed to open a humanitarian corridor" for the evacuation of Azerbaijani soldiers' bodies from battlefields," President Ilham Aliyev's foreign policy adviser Hikmet Hajiyev told journalists.
Armenian Defence Ministry Spokeswoman Shushan Stepanyan confirmed the handover mediated by Russia and the Red Cross and added that the Armenian side was ready to return bodies of slain Azerbaijani soldiers.