Le Monde published on 2 May 2016 an article titled "Les Ouigours menacent-ils la Chine en Afrique?" by Sebastien Le Belzic, who directs the Chinafrica site.
The article reports that members of the Uyghur minority group in western China have been seen with terrorist groups in Mali and Libya and may be involved with Boko Haram in Nigeria. There have been other reports of small numbers of Uyghurs joining the Islamic State in Syria and Libya, but this is the first report I am aware of that says they may be engaged in Mali and Nigeria. Le Monde suggests they may pose a direct threat to Chinese interests in Africa.