BEIJING (AFP) - China said on Friday (Sept 11) that the Islamic State in Iraq and Syria (ISIS) group was probably holding one of its citizens, adding the government had initiated an "emergency response", without giving details.

The militant group - which has become infamous for gruesome murders and mass killings - said on Wednesday (Sept 9) that it was holding a Chinese and a Norwegian hostage and demanded unspecified ransoms for their release.

"After initial verification, among the two who are reportedly kidnapped by the Islamic State, one of them matches the characteristics of a Beijing citizen who has gone missing overseas," Foreign Ministry spokesman Hong Lei told a regular briefing in Beijing.

ISIS identified the Chinese hostage as Mr Fan Jinghui, a 50-year-old consultant.

Mr Hong declined to be drawn on whether Beijing would pay a ransom for the hostage, saying only that the Chinese authorities had "initiated the emergency response mechanism" to deal with the crisis.

China "believes what the extremist group has done so far makes an enemy of all", the government-published China Daily wrote in an editorial on Friday, referring to ISIS.

"We pray the tragedies of the past will not be repeated this time," the paper added, alluding to past hostages murdered by ISIS.

In the case of each man, ISIS published an "advertisement" announcing that he was "for sale".

Under each man's photograph, it said: "To whom it may concern of the Crusaders, pagans, and their allies, as well as what are referred to as human 'rights' organisations, this prisoner was abandoned by his government, which did not do its utmost to purchase his freedom." At the bottom it said: "Whoever would like to pay the ransom for his release and transfer can contact the following telegram number," adding that it was a "limited time offer".

It did not say how much money was being demanded, nor when the opportunity to pay it would expire.