Nagorno-Karabakh shelling war armenia azerbaijan
© Bülent Kılıç/AFP/Getty ImagesRescue teams work at a site hit by a strike during fighting over the breakaway region of Nagorno-Karabakh, in the city of Ganja.
Azerbaijan has said at least 12 people have died after shelling levelled a row of homes in the city of Ganja, with 40 more wounded in a sharp escalation of the conflict with Armenia over the region of Nagorno-Karabakh.

The Azeri prosecutor general's office said that two shells hit apartment buildings in the country's second largest city. There has been no official reaction from Armenia as yet.

The attack on Saturday, which saw a second strike in another part of Ganja and a third reach the nearby strategic city of Mingecevir, came hours after Azerbaijani forces shelled the ethic Armenian separatist region's capital, Stepanakert.

The spike in violence further undermines international efforts to calm a resurgence of fighting between Christian Armenians and Muslim Azerbaijanis before it draws in regional powers Russia and Turkey.

Reporters in Ganja saw rows of houses turned to rubble by the shelling, and a rescue team remove black bags containing body parts from the scene. The strike shattered the walls and ripped the roofs off buildings in the surrounding streets.

People ran outside in shock and tears, stumbling through muddy alleys in their slippers, some wearing bathroom robes and pajamas.

One witness said he saw rescuers pull a small child, two women and four men from the debris in the minutes immediately after the strike.

"We were sleeping. The kids were watching TV," Rubaba Zhafarova, 65, said in front of her destroyed house. "All the houses around here are destroyed. Many people are under the rubble. Some are dead, some are wounded."

The attack came only six days after a missile struck another residential part of the city of more than 300,000 people, killing 10 civilians.

Hikmat Hajiyev, an assistant to Azerbaijan president Ilham Aliyev, tweeted that according to "initial information, more than 20 houses were destroyed" on Saturday.

Rescuers periodically called for silence so they could detect sounds of survivors as the hours passed, pulling out passports, keys, bracelets and items of clothing from the debris. They called in sniffer dogs and watered down the suffocating columns of dust with hoses from a fire truck.

"My wife was there, my wife was there," one man cried inconsolably while being walked toward an ambulance by a paramedic.

At around the same time in the city of Mingecevir, an hour's drive north of Ganja, reporters heard the impact of a huge blast that shook buildings.

Mingecevir is protected by a missile defence system because it is home to a strategic dam, and it was not immediately clear if the missile was destroyed in the air or had made impact.

The defence ministry said Mingecevir had come "under fire", but provided no other immediate details.

An Azerbaijani official said that a second missile hit a separate, industrial district of Ganja at around the same time. No immediate details about that second attack were known.

The decades-long Nagorno-Karabakh conflict re-erupted on 27 September in hotly disputed circumstances and has so far killed more than 700 people, including nearly 80 civilians.

The mountainous western region of Azerbaijan has remained under separatist ethnic Armenian control since a 1994 ceasefire ended a brutal war that killed 30,000.

But Armenia, which backs Nagorno-Karabakh but does not recognise its independence, has admitted that Azerbaijani forces have made important gains along the front in the past week.

The current escalation is the deadliest and longest since that six-year conflict.

The shelling of Stepanakert and the strikes on Ganja followed a joint call from Russian President Vladimir Putin and Turkish President Recep Tayyip Erdogan on Wednesday to "end the bloodshed as soon as possible".