The Reina nightclub attack in Istanbul on New Year’s Eve left 39 dead and dozens injured. When he was captured on January 17, Turkish officials said that the main suspect, Abdulkadir Masharipov, is an Uzbek national and a member of the Islamic State. Signs show that he might also be an ethnic Uyghur, and though the attacker carried out the shooting alone, at least 36 people who are thought to be involved have been detained since the assault, several of whom were Uyghurs. This attack, therefore, draws attention to an extremely sensitive topic of China-Turkey relationship: Uyghur engagement in terrorist violence.

Two clues lead to the possibility of the attacker’s Uyghur identity. First, the assumed name given to the attacker in Turkish media is Abu Muhammed Horasani. The second part of the name means “the man from Horasan.” Horasan, more often written as Khorasan, is an ancient name for an area encompassing much of central Asia, Afghanistan, Pakistan, and (sometimes) parts of western China; the area now has a significant Uyghur population. The Islamic State has revived the name, as has al-Qaeda’s Syria branch. Claimed to be an Uzbek national, Horasani hails from a country seen as a part of Khorasan and that has a large Uyghur population.

The second clue is that the Islamic State has claimed responsibility for the attack, as revenge for Turkish military intervention in Syria. The group has a history of using Turkic-language speaking recruits such as Uyghurs to conduct violence in Turkey. Two of the three attackers who carried out last year’s suicide bombing and shootings at Atatürk airport in Istanbul in June were Uzbek and Kyrgyz. Both are Turkic speakers. It is, therefore, not surprising that the major suspect might be a Uyghur this time.

China has not taken a leading role in countering global violent extremism, perhaps simply because China, unlike Western countries, has not been the main targets of recent major attacks. However, Uyghurs’ increasing involvement in ISIS global terrorist attacks might create opportunities to push China to invest more in counterterrorism efforts.

Beijing considers Chinese Uyghur individuals who promote separatism and advocate for independence (often known as members of the East Turkistan Independence Movement) as extremist terrorists. Not all Uyghurs have given up their hopes of becoming an independent nation after China took control over the region in 1949, This has cultivated the seed of ongoing mistrust between Uyghurs and Beijing. Particularly in South Xinjiang, many Uyghurs have been complaining about the margination and even persecution by the central government. In the past decade, hundreds of people have lost their lives due to conflicts between Uyghurs and Han, the ethnic majority in China.

Officially recognized as one of the 55 ethnic minorities in China, Uyghur Chinese speak a Turkic language. Most are Muslims. Though they can also be found in Central Asian countries, Uyghurs live primarily in the Xinjiang Uyghur Autonomous Region in China.

Many Uyghurs accuse the Chinese government of mistreating and discriminating against them, and are afraid that Chinese authorities in Xinjiang will prosecute or incarcerate them under the allegation of promoting separatism. A significant number of Uyghurs choose to leave China each year with the assistance of local smugglers. Sharing a similar language and culture, Turkey is an ideal destination. The Turkish government has sheltered Uyghur refugees since the 1950s. Of about 20,000 Uyghurs in Turkey, most settle in Istanbul, especially in the Zeytinburnu neighborhood. The two major ultranationalist groups, the Nationalist Movement Party (MHP)’s neo-fascist “Grey Wolves” and a similar group run by the rival Great Union Party (BBP), see Uyghurs as their “brethren.” These parties violently protest against Beijing’s treatment to their Uyghur minority, and lobby the Turkish government to grant Uyghur refugees legal status to stay. The Chinese government has never hesitated to criticize countries that accept Uyghur refugees. The Uyghur issue, as a result, has always created political conflicts between Turkey and China.

Among the Uyghurs who have fled, a small number of them found a warm welcome with the Islamic State group. The extremist group has been taking advantage of the tension between Uyghurs and Beijing. Its propaganda videos, some even in Mandarin, have leaked in China to recruit Chinese Muslims to join the mission. These videos seem to provide a solution to Uyghur militants’ resentment to Beijing. They join and are trained by the group in Syria and Iraq with the ultimate goal to fight back in China.

The growing number of Uyghur ISIS members has raised concerns for the Chinese government. Since most Uyghurs who join ISIS share a strong dissatisfaction toward the Communist Party-led central government, their joining of extremist groups is seen as increasing the risk of a terrorist attacks in China. The total number of Uyghurs in ISIS is a matter of dispute. Security experts at the United Nations and Western experts challenge Chinese officials’ estimation of about 300 or more with the group. According to this report, 114 Uyghurs joined ISIS from mid- 2013 to mid-2014, almost all from China.

There have been a number of arrests since the Reina nightclub attack. On January 13, 2017, a Turkish court announced the arrest of two Uyghur Chinese that might be linked to the attack. Though the nationality of the main suspect has been identified, it is still unknown whether or not he is an ethnic Uyghur.

If he is confirmed to be an ethnic Uyghur, especially if he is found to have links to Uyghur Chinese, China might use this attack to re-address the issue of Uyghur terrorism, and to justify its prosecution of Uyghur terrorist suspects in the past. It may also use this to persuade the Turkish government to cooperate more on the Uyghur migrant issue: for instance, to stop accepting more Uyghur refugees and to repatriate detained ones. Turkey might be more willing to work with China than in the past if domestic attitudes towards the Uyghur population change after this national tragedy. Although China has not been a major figure in the global counter-terrorism regime, this could push them toward a more active role.

Ivy Yang is an intern at the Atlantic Council’s Rafik Hariri Center.

Image: Photo: Turkish flags are placed near the entrance of Reina nightclub in Istanbul, Turkey, January 17, 2017. REUTERS/Osman Orsal