The mother of Xu Xiang, China’s high-flying hedge fund manager now in detention on suspicion of insider trading, has had her shares worth 4.3 billion yuan (HK$5.2 billion) frozen, . Xu, 37, the founder and general manager of Zexi Investment and dubbed “China’s Warren Buffett”, was arrested by police on a highway on November 1 on charges including insider trading and stock market manipulation. His mother Zheng Suzhen’s shares in the retail firm Wenfeng Great World Chain Development and Daheng New Epoch Technology were frozen by the public security bureau. READ MORE: Questions mount over Chinese billionaire hedge fund manager's big stock picks The two companies announced on Monday night that they had received notice from the Shanghai Stock Exchange saying that Zheng’s shares would be frozen for two years starting from Monday. Zheng, the biggest shareholder of Daheng, owns close to 30 per cent of its shares totalling 2.1 billion yuan. She owns nearly 15 per cent of shares in Wenfeng, amounting to over 2.1 billion yuan. Daheng issued a statement three days after Xu’s arrest saying he was not involved in the firm’s daily operations and did not hold any positions in the company. READ MORE: Zexi Investment's Xu Xiang: The self-made man with the Midas touch Police have launched a series of inquiries into allegations of market manipulation after the huge falls in share prices in mainland China over the summer. Xu’s stock picks for the targets of government rescue funds have fuelled allegations of widespread insider trading and market manipulation during the slump in stock values. Five of Zexi Investment’s funds reported at least 20 per cent growth in net asset value as the benchmark share indicator sank 35 per cent in three weeks from mid June.