Muslim extremists from the Xinjiang Uygur autonomous region have gone to the Middle East for training and some may have crossed into Iraq to take part in the upsurge of violence there, China's special envoy for the Middle East, Wu Sike, said on Monday.

China has repeatedly expressed concern about the upsurge in violence in Iraq and the march of the Islamic State of Iraq and the Levant, which has seized much of the north of the country as Baghdad's forces there collapsed.

ISIL, alternately translated as the Islamic State of Iraq and Syria, or ISIS, has proclaimed the establishment of a caliphate on land it has captured in Syria and Iraq.

Wu, who has recently returned from the region, said China is extremely worried about the role of extremist groups in the fighting in Syria and Iraq.

"Several hot spot issues in the Middle East have provided living space for terrorist groups. In particular, the crisis in Syria has turned this country into a training ground for extremists from many countries," he said.

"These extremists come from Islamic countries, Europe, North America and China. After being immersed in extremist ideas, when they return home they will pose a severe challenge and security risk to those countries," added Wu, who has 40 years of diplomatic experience in the Middle East.

While many analysts question whether these groups could accumulate the abilities that China is worried about, some people from China's Uygur ethnic group have made their way to Afghanistan and Pakistan in recent years.

Wu did not give a figure for how many Chinese citizens may be in the Middle East either fighting or being trained, saying that he understood from foreign media reports that the number is about 100.

"Mostly they are East Turkestan elements," Wu said.

"They won't necessarily all return (to China). Some will remain to participate in the conflict, perhaps crossing into Iraq," he said, without elaborating.

US intelligence agencies estimate that about 7,000 of the 23,000 violent extremists operating in Syria are foreign fighters, mostly from Europe.

In June, China's Guangming Daily reported the involvement of ethnic Uygur terrorists in the ongoing Syrian civil war.

All the terrorists, about 100, are members of the East Turkestan Islamic Movement - a terrorist organization that pursues the secession of Xinjiang from China, the newspaper quoted a report by Israel's Meir Amit Intelligence and Terrorism Information Center as saying.

Foreign terrorists have accumulated firsthand battleground experience in the Syrian civil war and will implement what they have learned into waging terrorist attacks or organizing terror groups in their home countries, and that will pose grave menace to these countries, the Israeli report said.

Wu said China would do all it could to help Middle Eastern countries fight terror as this was also in China's best interests.

"China is a victim of extremist, terrorist activities, and our support for fighting terrorism in this region is beneficial to us, too. As a result, China and those countries are in a closely knit community of shared interests."

Wu said that despite the violence, he was confident in Iraq's future and China's involvement in its energy sector.

"In the long run, China has confidence in the political reconciliation and economic development of Iraq, so we have confidence in the future of this (energy) cooperation," he said.

Reuters - China Daily

(China Daily 07/29/2014 page3)