I am still fearful of them." He tried to promote eunuchs that he trusted such that they would wield power, but according to himself, this tactic was not particularly successful, as the eunuchs that he promoted, once they became highly ranked, joined with the less obedient powerful eunuchs as well. At one point, he discussed with Linghu the possibility of massacring the eunuchs, which Linghu opposed because Linghu feared that the innocent as well as the guilty would be harmed; Linghu instead suggested gradually reducing the eunuchs' numbers. Linghu's proposal was leaked to the eunuchs, and the eunuchs were said to continue to despise the imperial officials because of this. Late in Emperor Xuanzong's reign, he came to favor certain alchemists who had promised him immortality, taking regularly the cinnabar-based pills which they manufactured and prescribed. It was said that as a result of poisoning by these pills, he became paranoid and easily angered, and by 859, as a further side effect of the consumption of these toxic, mercurial elixirs, he had developed a large ulcerous boil on his back, rendering him bedridden and unable to conduct meetings with his chancellors and other officials. He entrusted Li Zi to three high-level eunuchs that he favored—the directors of palace communications (Shumishi) Wang Guizhang () and Ma Gongru () and the director of the southern court affairs (宣徽南院使, Xuanhui Nanyuanshi) Wang Jufang (). After Emperor Xuanzong died, Wang Guizhang, Ma, and Wang Jufang did not initially announce his death, and were set to send one of the eunuch commanders of the Shence Armies (), Wang Zongshi (), who was not on good terms with them, out of Chang'an to Huai'nan Circuit (淮南, headquartered in modern Yangzhou, Jiangsu) to serve as the eunuch monitor for Huai'nan. Wang Zongshi, however, reacted by intruding into the palace; finding that Emperor Xuanzong had already died from Chinese alchemical elixir poisoning, he arrested Wang Guizhang, Ma, and Wang Jufang for falsely issuing edicts, and then put them to death. He welcomed Li Wen to the palace, and then issued an edict in Emperor Xuanzong's name creating Li Wen crown prince and changing his name to Li Cui. The next day, Emperor Xuanzong's death was announced, and Li Cui became emperor (as Emperor Yizong). Relations with Muslims During Sulaiman al-Tajir's stay at the city of Guangzhou he noted that the Chinese used fingerprint records to maintain the identities