The Hang Seng Index fell 1.18% or 293 points during the morning session to 24,668 points, while the Hang Seng Tech Index declined 2.4%. Morning trading volume on the Hong Kong market reached HKD 196.2 billion.

Stocks in the Kingboard group saw robust gains, driven by rising prices for copper-clad laminate (CCL). KB Laminates Holdings Ltd (HKEX: 01888) surged 10.78%, and Kingboard Holdings Ltd (HKEX: 00148) jumped over 12%.

Construction machinery stocks were among the top gainers. Excavator sales in May grew faster than expected, with exports maintaining strong momentum. Sany Heavy Industry Co., Ltd. (HKEX: 06031) rose 5%, and Zoomlion Heavy Industry Science And Technology Co.,Ltd. (HKEX: 01157) advanced 3.77%.

Shougang Lanze Biotechnology Co., Ltd. (HKEX: 02553) bucked the market trend with a gain of over 6%. As a leader in carbon capture, utilization, and storage (CCUS), the company is positioned to benefit from the rapid expansion of the sustainable aviation fuel (SAF) market.

Quantgroup Holdings Ltd (HKEX: 02685) soared more than 22%. Its subsidiary, Silicon Intelligence, is expanding into full-scenario embodied intelligent robotics. The stock's rise was also supported by a voluntary extension of the lock-up period by its controlling shareholder.

Trgiant Group Ltd (HKEX: 01300) climbed over 11% again. Its share price has increased more than tenfold this year, bringing its total market capitalization close to HKD 90 billion. The company is involved in the large-scale deployment of AI data center (AIDC) facilities for a client.

Estun Automation Co.,Ltd. (HKEX: 02715) saw intraday gains exceeding 12%, maintaining its position as the top seller of industrial robots in the Chinese market.

51World, Inc. (HKEX: 06651) rose 11%. Following NVIDIA's release of Cosmos 3, the company's 51Sim platform is expected to continue benefiting from industry development.

Shandong Molong Petroleum Machinery Company Limited (HKEX: 00568) surged over 15% as international oil prices spiked this morning after Iran launched an attack on Israel, the first in two months.

Lung Fung Group Limited (HKEX: 02290), a Hong Kong-based drugstore and cosmetics retailer, fell another 10%+, with its share price halving just two trading days after its IPO.

MGM China Holdings, Ltd. (HKEX: 02282) dropped 4.9% after Pansy Ho divested her entire stake in MGM Resorts International for a total consideration of approximately USD 140 million.

Airlines stocks declined again. The International Air Transport Association (IATA) lowered its global airline industry net profit forecast for this year, projecting a nearly 40% increase in fuel expenses. China Eastern Airlines Corporation Limited (HKEX: 00670) fell 4.6%, and Air China Limited (HKEX: 00753) declined 3.3%.

Gold stocks fell across the board. Strong U.S. non-farm payrolls data fueled expectations for further interest rate hikes, pushing spot gold prices below USD 4,300 at one point. Lingbao Gold Co., Ltd. (HKEX: 03330) dropped 6.7%, and Zijin Gold International Resources Ltd. (HKEX: 02259) slid 7.5%.