(Bloomberg) -- BYD Co., the Chinese electric-car maker backed by Warren Buffett, asked the police to investigate a person who allegedly posed as an employee and signed unauthorized marketing contracts in the company’s name.

China’s biggest maker of new-energy vehicles said the person’s actions have damaged its reputation and harmed related parties. The person isn’t an employee or never has been, and BYD has never authorized the person to conduct business in its name, the Shenzhen-based company said in a statement to the Hong Kong stock exchange Monday.

The carmaker also said it reported to the police a forged company seal, which may have been used to stamp contracts that the person awarded. The person conducted marketing activities in BYD’s name over the past three years, The Paper reported on July 15.

BYD and other makers of electric cars have been accelerating marketing efforts to help attract consumers in the world’s biggest market for such vehicles. BYD signed up Leonardo DiCaprio to represent the company’s new-energy vehicles in 2016 and became the official global car and bus partner to English football club Arsenal in April.

BYD fell by as much as 5.1 percent in Hong Kong, the biggest intraday plunge since April 30.

To contact Bloomberg News staff for this story: Tian Ying in Beijing at ytian@bloomberg.net

To contact the editors responsible for this story: Anand Krishnamoorthy at anandk@bloomberg.net, Ville Heiskanen, Sam Nagarajan

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