The sudden death of Tang Xiao'ou, a key figure behind China's facial recognition technology and a cofounder of SenseTime Group, is the latest challenge to face the US-sanctioned artificial intelligence (AI) giant, with its shares losing 11 per cent in Hong Kong on Monday. Shares of SenseTime, once held up as a model of China's AI capabilities thanks to the strong research credentials of Tang, a professor with the Chinese University of Hong Kong, have dropped to their lowest-ever level since its