The two nationals were reportedly abducted from Quetta area in Pakistan.

Chinese and Pakistani authorities have started investigation the claim made by the militant group.

A Pakistani senior government official, on condition of anonymity, told Dawn.com that an investigation into the IS claim is underway.

Chinese officials have expressed their concern over the incident.

Speaking on the issue China's Foreign Ministry Spokesperson Hua Chunying said in a statement: "We have noted the relevant report and are highly concerned about that. We have been trying to rescue the two hostages during this period of time. The Chinese side is trying to learn more about and verify the situation by all means, including via the Pakistani side. The Chinese side firmly opposes kidnapping of civilians, terrorism and extremely violent acts in all forms."

Meanwhile, SITE Intel Group website said: "The Islamic State’s (IS) ‘Amaq News Agency reported that group fighters killed two Chinese nationals who were being held in Balochistan province of Pakistan."