ISLAMABAD: All Chinese nationals, who were linked to a Korean language centre in Quetta, have been evacuated after gunmen kidnapped two Chinese nationals last month, sources said on Friday. The Islamic State claims it has killed Chinese pair abducted on May 24. Both China and Pakistan have to verify the claim as yet. The slain Chinese were teachers at a centre being run by a South Korean national and his wife. Chinese Foreign Ministry on Friday expressed grave concern over the reported killing of two Chinese nationals, according to Xinhua news agency. “We have taken note of relevant reports and we express our grave concern. We have been trying to rescue the two kidnapped hostages over the past days,” Foreign Ministry spokeswoman Hua Chunying said in response to the reports. “The Chinese side is working to learn about and verify relevant information through various channels, including working with Pakistani authorities,” she said, and added, “The Chinese side is firmly opposed to the acts of kidnapping civilians in any form, as well as terrorism and extreme violence in any form.” Sources said 11 Chinese national, who were part of the language centre, have been evacuated after the kidnapping. However, Chinese staff working on CPEC projects has not been withdrawn and are performing their duties as per routine. A group of 10 Chinese nationals had been associated with the Korean language centre ARK in Quetta. A Korean national, who is stated to have been living in Quetta on a business visa for last four years, had received NOC for his centre from the provincial home department. The centre, which has been closed now, was offering Korean, Chinese and Urdu language courses. Sources said the Korean embassy in Islamabad has called head of the centre and seven other nationals linked to it. The centre had hired private security gaurds this month. Officials in Quetta insist that the Chinese had been offered security recently, but the pair had declined the offer. A purported video of the Chinese nationals is being circulated in Quetta, showing graphic images of the kidnapped pair. On Thursday, Pakistan Army released details of a major operation against Islamic State and Lashrake-Jhangivi Al-Almi (LeJA) in Balochistan. The military had stated there were reports of 10-15 terrorists of LeJA hiding in caves near Isplingi ( Koh-i-Siah/Koh-i-Maran), 36 kilometres Southeast of Mastung. However, LeJA spokesman Ali bin Sufyan said on Friday that the organisation had no relations with the Islamic State Khorasan and that those killed in the military operation in Mastung’s Isplingi area were members of the IS.