China Building Materials (3323.HK) tumbled more than 8% during regular Hong Kong trading to HK$6.05, with turnover exceeding HK$1.06 billion.

The stock had surged over 20% yesterday following market speculation about the company's new materials assets—Sinoma Technology and Zhongfu Shenying—in the electronic fabric supply chain for AI servers. Today's decline represents profit-taking after the recent rally.

The broader Hang Seng Index lost more than 300 points, slipping below the 24,000-point mark amid concerns that Federal Reserve officials expect rate hikes this year, weighing on sentiment toward interest-rate-sensitive sectors.