South Korean stocks closed 0.55 percent lower on Monday as key automakers Hyundai Motor and Kia Motors tumbled after U.S. officials found they exaggerated the fuel efficiency of their latest models, analysts said. The local currency slipped against the U.S. dollar.

The benchmark Korea Composite Stock Price Index lost 10.5 points to 1,908.22. Trading volume was light at 336 million shares worth 4.54 trillion won ($4.16 billion), with decliners outnumbering gainers 447 to 369.

“Since Hyundai and Kia are companies with big market caps, their fuel efficiency issue weighed on the main index,” said Cho Byung-hyun, an analyst at Tong Yang Securities Inc. “Moreover, investors were overall cautious ahead of the U.S. presidential election,” said Cho.

Automakers led the fall, with the country’s top player Hyundai Motor dropping 7.21 percent to 199,500 won and its smaller affiliate Kia Motors sinking 6.94 percent to 56,300 won.

On Sunday, the two leading carmakers said in an apology that they made procedural errors during testing operations, which led to inaccurate fuel economy ratings for roughly 900,000 cars sold in the U.S. between 2010 and 2012.

The move came after the U.S. Environment Protection Agency said their recent study found the two car makers overstated gas mileage figures of their latest models.

While the incident is likely to hurt the company’s corporate image, the amount of compensation, estimated at a combined $90 million on an annual basis, is unlikely to hurt the company’s financial status, KB Securities Co. analyst Shin Chung-kwan wrote in a report.

Shares of Hyundai Motor affiliates also took a blow from the event, with Hyundai Engineering & Construction falling 2.28 percent to 64,200 won and Hyundai Steel losing 1.4 percent to 77,200 won.

In contrast, tech shares mostly closed higher. Market bellwether Samsung Electronics rose 1.06 percent to 1,341,000 won and display giant LG Display gained 1.16 percent to 34,750 won.

South Korea’s No. 2 mobile carrier KT ended 3.64 percent higher at 38,400 won after releasing its third-quarter earnings. The company reported a 45.6 percent rise in net profit on the back of its growing long-term evolution subscriber base.

The local currency closed at 1,091.2 won against the greenback, down 0.3 won from Friday’s close, as global economic uncertainties reemerged ahead of the U.S. presidential vote, dealers said. (Yonhap News)