Hyundai Mobis Co., South Korea's top auto parts maker, said Friday its third-quarter earnings plunged 20 percent from a year earlier due mainly to falling sales in China and other major countries.

Net profit stood at 621 billion won (US$552 million) in the July-September period, compared with a profit of 776 billion won a year earlier, the company said in its regulatory filing.

Operating profit also shed 8.3 percent on-year to 670 billion won in the third quarter, while sales rose 2.9 percent to 8.48 trillion won, it said.

Shortened working days and a slump in China were attributable to the weak earnings, Hyundai Mobis said.

In the first nine months of the year, its sales stood at 26.03 trillion won, with its operating income standing at 2.07 trillion won.

The revenue from modules and key auto parts came to 21.3 trillion won in the first nine months of the year, up 1.9 percent from a year earlier, the company said. Its returns from warranty-related production came to 4.7 trillion won over the cited period, up 0.5 percent on-year.

Shares of Hyundai Mobis were trading at 237,500 won on the Seoul bourse as of 11:35 a.m., up 1.06 percent from the previous session's close. (Yonhap)