Tokyo stocks tumbled Thursday, with the benchmark Nikkei stock index falling below the 63,000 mark for the first time since July, as investors locked in profits amid lingering concerns over the sustainability of artificial intelligence-related investments.

Hong Kong's Hang Seng Index fell 679.94 points, or 2.87 percent, to 22,971.93 points in the morning session on Thursday.

Chinese stocks opened mixed on Thursday, with the benchmark Shanghai Composite Index up 0.04 percent to open at 3,714.48 points.

The ChiNext Index, tracking China's Nasdaq-style board of growth enterprises, was down 0.25 percent to open at 2,687.94 points Thursday.

The Hang Seng Index lost 138.08 points, or 0.58 percent, to open at 23,513.79 points on Thursday.

U.S. stocks closed higher on Wednesday as AI shares rebounded following SpaceX's quarterly results.The Dow Jones Industrial Average rose 360.21 points, or 0.69 percent, to 52,856.09. The S&P 500 added 44.6 points, or 0.58 percent, to 7,757.17. The Nasdaq Composite Index increased by 278.04 points,

Hong Kong's Hang Seng Index fell 0.9 percent to close at 23,651.87 points on Wednesday.

Tokyo stocks rose Wednesday, although gains were limited as investors remained cautious ahead of earnings reports from major U.S. technology companies.The benchmark Nikkei stock index, the 225-issue Nikkei Stock Average, ended up 545.82 points, or 0.85 percent, from Tuesday at 64,621.24.

Chinese stocks closed lower on Wednesday, with the benchmark Shanghai Composite Index down 0.6 percent to 3,713.03 points.

Hong Kong's Hang Seng Index rose 271.37 points, or 1.14 percent, to open at 24,139.11 points Wednesday.

The ChiNext Index, tracking China's Nasdaq-style board of growth enterprises, was up 0.28 percent to open at 2,746.84 points Wednesday.

The STAR Composite Index, which reflects the performance of stocks on China's sci-tech innovation board, opened 0.9 percent higher at 1,618.38 points on Wednesday.

Chinese stocks opened higher on Wednesday, with the benchmark Shanghai Composite Index up 0.14 percent to open at 3,740.57 points.

Hong Kong's Hang Seng Index fell 1.32 percent to close at 23,867.74 points on Tuesday.

The STAR Composite Index, which reflects the performance of stocks on China's sci-tech innovation board, closed 2.13 percent higher at 1,603.89 points on Tuesday.

The ChiNext Index, tracking China's Nasdaq-style board of growth enterprises, lost 0.26 percent to close at 2,739.2 points Tuesday.

Chinese stocks closed mixed on Tuesday, with the benchmark Shanghai Composite Index up 0.12 percent to 3,735.37 points.The Shenzhen Component Index closed 0.14 percent lower at 11,801.29 points.

U.S. stocks ended mixed on Monday as technology shares rebounded from their steepest weekly drop since June.The Dow Jones Industrial Average edged down 36.38 points, or 0.07 percent, to 51,966.03. The benchmark S&P 500 added 31.29 points, or 0.41 percent, to 7,690.73, while the tech-heavy Nasdaq

Tokyo stocks ended mixed Monday, as renewed concerns over heavy investment in artificial intelligence infrastructure weighed on the Nikkei index, while bargain hunting helped the broader Topix index edge higher.

The STAR Composite Index, which reflects the performance of stocks on China's sci-tech innovation board, closed 0.86 percent lower at 1,570.40 points on Monday.