Hyundai Heavy Industries Co., South Korea's leading shipbuilder, said Thursday its third-quarter earnings soared almost 30 percent from a year earlier on a one-time factor.

  Net profit reached 729 billion won ($666 million) on a consolidated basis in the July-September period, compared with a profit of 562 billion won a year earlier, the company said.

  Sales edged up 0.8 percent on-year to reach 13.1 trillion won, while operating income dropped 35 percent to 594 billion won over the cited period, it said.

   The rise in the third-quarter net profit was mainly due to gains from a stake sale in Hyundai Motor Co., the country's leading automaker.

   In July, Hyundai Heavy sold 3.2 million shares of Hyundai Motor in a block sale, pocketing around 700 billion won.

   Hyundai Heavy said its third-quarter operating income sank from a year earlier as it built low-priced ships.

   Shares of Hyundai Heavy closed at 228,500 won on the Seoul bourse, down 0.44 percent from the previous session's close. The third-quarter business results were released after the market closed. (Yonhap News)