Nagorno-Karabakh’s largest city came under heavy shelling on Thursday, three sources working there said, as Reporters Without Borders called for the safe evacuation of civilians who it says are trapped in Stepanakert. Writing on Twitter, Reporters Without Borders, a nonprofit group, called on the United Nations, the Council of Europe and Azerbaijan “to do everything possible” to allow an evacuation of civilians, including 80 local and foreign journalists. At least 1,000 people and possibly many more have been killed since fighting broke out on Sept. 27 in Nagorno-Karabakh, a mountainous enclave internationally recognised as part of Azerbaijan but populated and controlled by ethnic Armenians. A freelance reporter working in Stepanakert, who did not wish to be identified, told Reuters by telephone that the city was under shelling before turning off the handset to avoid the risk of detection. “The air raid siren hasn’t stopped all day,” a second reporter said, again speaking by telephone from Stepanakert. A third journalist, from France, said that some reporters had left the city via a northern route because the main road to the Armenian capital, Yerevan, via the strategic region of Lachin was also under fire. The ethnic Armenian-controlled Nagorno-Karabakh Emergency and Rescue Service said on Thursday that Stepanakert - called Khankendi by Azerbaijan - was being shelled by Azeri forces. It said heavy artillery had also been used in the town of Martuni, known by Azerbaijan as Khojavend, while Shushi, or Shusha - the enclave’s second-largest city - had been damaged by shelling. Azerbaijan’s defence ministry denied these accusations. It said the city of Terter and a nearby village, as well as villages in the Aghdam region in the east of the conflict zone, had been shelled. Ethnic Armenian forces denied this. Azerbaijan’s defence ministry also said combat operations continued “with varying intensity” around Aghdere - Martakert, in Armenian - and Khojavend. The worst fighting in the South Caucasus for more than 25 years has underlined the influence of Turkey, an ally of Azerbaijan, in a region once part of the Soviet Union and long dominated by Moscow, which has a defence pact with Armenia. Three ceasefires have failed to hold while attacks by both sides resumed within hours of an agreement by the warring sides last Friday to avoid targeting civilians. The ethnic Armenian-controlled Nagorno-Karabakh defence ministry says 1,177 of its troops have been killed since Sept. 27. Azerbaijan does not disclose its military casualties, while Russia has estimated 5,000 deaths on both sides.