BAKU/YEREVAN -- Heavy fighting between Armenian and Azerbaijani forces continues despite renewed international calls for a cease-fire in and around the breakaway region of Nagorno-Karabakh.
A brief lull in overnight fighting was interrupted by a barrage of rocket fire on Nagorno-Karabakh's capital, Stepanakert (Xankandi), and a "large-scale attack" by Azerbaijani forces along the southern front, Armenian Defense Ministry spokeswoman Shushan Stepanian said.
Azerbaijan said Armenian forces targeted several of its regions.
Since fighting erupted on September 27, the two sides have reported at least 240 deaths, including dozens of civilians. The actual toll is expected to be much higher, as both sides claim to have inflicted heavy military casualties. Each side has accused the other of targeting civilians.
The hostilities have increased concern that a wider conflict could drag in regional power Turkey, which is Azerbaijan's closest ally, and Russia, which has a defense pact with Armenia.
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On October 5, Russia, France, and the United States -- the co-chairs of the Organization for Security and Cooperation in Europe's (OSCE) so-called Minsk Group, which has spearheaded peace efforts over Nagorno-Karabakh since the early 1990s -- reiterated their call for an immediate cease-fire in and around Nagorno-Karabakh.
The three powers described the escalating conflict as an "unacceptable threat" to the region's stability.
Turkey has openly supported Azerbaijan, saying it will be at Baku's side "at the negotiating table and on the field" as the two Turkic countries seek to create facts on the ground to strengthen any negotiating position.
Brushing off calls for a cease-fire, Turkish Foreign Minister Mevlut Cavusoglu met with Azerbaijani President Ilham Aliyev in Baku on October 6, vowing to deepen the country's involvement as it criticized the Minsk Group.
"There should be no doubt that when needed, we will act like one state. Turkey is Azerbaijan, Azerbaijan is Turkey," Cavusoglu tweeted on October 6.
Cavusoglu said in Baku that any cease-fire proposal was "no different" from previous ones and would not address what he described as violations of Azerbaijan's territorial integrity.
"OK, let the cease-fire take place but what will be the result? Can you [the world] tell Armenia to immediately withdraw from Azerbaijani territories or can you produce solutions for its withdrawal? No," he said after a meeting with his Azerbaijani counterpart, Ceyhun Bayramov.
Azerbaijan has demanded Armenian forces withdraw from Nagorno-Karabakh and surrounding Azerbaijani territories, saying that it would not end military action until its demands are met. Those conditions would be nearly impossible for Armenia to accept.
Some analysts have suggested Turkish President Recep Tayyip Erdogan is gambling that his support for Azerbaijan will change the dynamics of the dispute over Nagorno-Karabakh and give Ankara greater say in the region, just as its military interventions in Libya and Syria have put it in a key position to deal with Russia.
"Much like in Syria and in Libya, Erdogan may be hoping for a deal with Putin. The Turkish president is biding his time until the Azeris make, and consolidate, territorial gains," Dimitar Bechev, a nonresident fellow at the Middle East Institute's Frontier Europe Initiative Center, wrote in an analysis.
"If and when that happens, he could propose a bilateral peace initiative to Russia. This would be a symbolic coup for Turkey, elevating the country to a major player in the South Caucasus, on par with co-chairs of the OSCE's Minsk Group, Russia, the U.S., and France," he added.
Meanwhile, Armenian Prime Minister Nikol Pashinian discussed the fighting in a phone conversation with Russian President Vladimir Putin.
The Kremlin said in a statement that Putin "once again stressed the need for ceasing hostilities."
"So far the situation is deteriorating. People are still getting killed, which is absolutely unacceptable," Kremlin spokesman Dmitry Peskov told journalists.
Armenia announced that Russian Prime Minister Mikhail Mishustin is expected in Yerevan on October 8, although the government said the planned visit was "completely unrelated" to the current fighting.
Meanwhile, Britain and Canada said there was an "urgent need to end the continuing military action in and around the Nagorno-Karabakh conflict zone" and called for all parties to return to the negotiating table.
"We are particularly concerned by reports of the shelling of civilian areas and wish to express our condolences to the families of those who have tragically lost their lives," Foreign Secretary Dominic Raab and Canadian Foreign Minister François-Phillippe Champagne said.
Azerbaijan and Armenia have accused each other of starting the fighting.
Analysts say Azerbaijan had been engaged in a military build-up since a flare-up in fighting in July and had an incentive to disrupt the status quo amid long-stalled Minsk Group negotiations over the territory.
The fighting is the most intense since a 1994 cease-fire, with ground troops, artillery, drones, rockets and tanks in action across the entire line of contact separating Armenian and Azerbaijani forces.
Baku says Azerbaijani cities outside Nagorno-Karabakh have been hit, and Armenia has accused Azerbaijan of targeting densely populated areas.
Both have denied targeting civilians, but rights groups have warned against the use of banned munitions such as cluster bombs.
Amnesty International said on October 5 that its experts were able to identify cluster munitions that appear to have been fired by Azerbaijani forces into residential areas of Stepanakert, the largest city in Nagorno-Karabakh.
"The use of cluster bombs in any circumstances is banned under international humanitarian law, so their use to attack civilian areas is particularly dangerous and will only lead to further deaths and injuries," the London-based human rights watchdog said in a statement.
Azerbaijan and Armenia have been locked in a conflict over the mountainous region since the waning years of the Soviet Union. They fought a war that ended in 1994 with an uneasy cease-fire and an estimated 30,000 killed.
Nagorno-Karabakh is internationally recognized as Azerbaijani territory, but it is controlled by ethnic Armenian separatists with close ties to Yerevan. Armenian forces hold control over seven regions adjacent to Nagorno-Karabakh.