Shares of Baidu, the US-traded Chinese internet giant, slumped almost 8 per cent on the Nasdaq as China’s internet watchdog started investigating the company’s search system. The New York-listed Baidu stock dropped 7.92 per cent to US$178.91 on heavy trading volume, wiping out US$5.3 billion value from its book – after news broke on Monday that its CEO Robin Li would be summoned by the Chinese authorities over the death of a student. China launches probe into Baidu over paid search listings after student dies following cancer treatment sourced online The investigation came after a public outcry over the death of 21-year-old university student Wei Zexi, a cancer patient who sought treatment in a hospital whose treatment programme had appeared on top of the Baidu search engine’s results. Baidu charges advertisers for ranking them high in its online searches. Wei, who had sarcoma, a rare cancer in soft tissues, opted for a form of immunotherapy – an experimental treatment that resulted in him losing critical time for cure. He died last month.