China’s stocks dropped to a three-week low, as traders reduced bets on stocks with outsize gains before a weeklong holiday to mark the 70th anniversary of the founding of the Communist nation. The Shanghai Composite Index fell 0.9 per cent to 2,929.09 on Thursday, the lowest level since September 2. A gauge of smaller companies trading on Shenzhen’s ChiNext board tumbled 2.9 per cent, the biggest loss in four months. Hong Kong’s Hang Seng Index added 0.4 per cent to 26,041.93. Sell-offs gained strength among traders who opted to exit the market ahead of the weeklong National Day holiday starting on October 1. The hangover of the US-China trade war and the political unrest in Hong Kong are among the key market-moving factors that investors still need to keep a close watch when China’s markets are closed for holiday from October 1 to 7. “Investors are selling to steer clear of uncertainty that may pop up in the coming days,” said Wu Kan, an investment manager at Soochow Securities in Shanghai. “They are pocketing gains for safety sake.” Stocks that had been riding the hottest investment themes this year bore the brunt of the selling. Jiangxi Zhengbang Technology and other pork producers slumped on fears their share price gains were excessive and there would be more insider selling. Jiangxi Zhengbang slumped by the 10 per cent daily limit to 14.56 yuan in Shenzhen, paring its advance to 174 per cent this year, while Muyuan Foodstuff also sank by that much to 62.64 yuan, trimming its annual gain to 118 per cent. New Hope Liuhe, controlled by billionaire Liu Yonghao, tumbled 10 per cent to 16.04 yuan after the stock had surged 145 per cent year to date. Rising pork prices amid the spread of African swine fever had fuelled a rise in pig-farming stocks this year. Prices of the meat, already at record highs, show no sign of weakening, as the stock of breeding sows continues to fall and the work on vaccines for the disease is still some way off. The hefty gains in stock prices already prompted some senior executives to cash out of stocks. Jiangxi Zhengbang said this week that chief financial officer Zhou Jinming plans to sell up to 27,500 shares in the company within six months. JL MAG Rare-Earth, a producer of material used in smartphones and electric cars, slid by the 10 per cent daily limit for a fourth straight day to 41.39 yuan. Shenzhen Yuanzhi Fuhai No 9 Investment, the fifth-largest shareholder, plans to sell a 3 per cent stake in the company within the following three months, according to an exchange statement. JL MAG also said earlier this week that the lock-up period of a nearly 45 per cent stake held by pre-IPO investors in the company expired on Monday, potentially increasing the supply of shares available for public trading. Shares of JL MAG had jumped more than threefold after President Xi Jinping visited the company in May. China CIFCO Investment also plunged by the 10 per cent daily cap to 11.86 yuan after the company said it had scrapped a plan to buy a majority stake in International Futures, a futures brokerage. The purchase was terminated because the company could not reply to the feedback by the regulator on the acquisition within the specified time frame. In Hong Kong, New World Development rose 2 per cent to HK$10.20, the biggest gain in two weeks, even as activist investor David Webb criticised the company’s land donation as a move that would harm shareholders’ interests and a potential breach of fiduciary duty.