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SEOUL, May 4 (Reuters) - China vehicle sales for South Korea's Hyundai Motor and Kia Motors Corp both tumbled more than 60 percent year-on-year in April, two sources briefed on the matter told Reuters, marking the second straight monthly drop due to political tensions.
Hyundai Motor Co saw sales skid 64 percent to 35,009 vehicles last month compared to a year earlier, the sources, who declined to be identified as the numbers were not public, said on Thursday.
Sales from affiliate Kia Motors Corp dropped 68 percent to 16,050 vehicles.
A spokesman representing both companies declined comment.
South Korean companies, from automakers to retailers and cosmetics firms, have been hit in China by a nationalist backlash over Seoul's decision to deploy a U.S. missile defence system, which has a powerful radar capable of penetrating Chinese territory.
Chinese state media have reacted with anger and boycott threats, after South Korea's Lotte Group in late February approved a land swap with the government that allows authorities to deploy the U.S. Terminal High Altitude Area Defense (THAAD) system in response to the North Korean missile threat.
In March, Hyundai and Kia saw their combined China sales slump by 52 percent from a year earlier. China accounts for about a quarter of their total sales.
With a heavy reliance on sedans and a poor brand image in the world's largest auto market, Hyundai and Kia have already been losing market share to local Chinese brands that are armed with cheaper SUVs. (Reporting by Hyunjoo Jin; Editing by Clarence Fernandez and Randy Fabi)