Billionaire investor Warren Buffett (R) and Microsoft founder Bill Gates (C) tour in a plant of BYD Auto, a Chinese carmaker, in Huizhou, South China's Guangdong province, Sept 28, 2010. Warren Buffett and Bill Gates visited BYD's plants in Shenzhen and Huizhou of Guangdong province Tuesday. [Xinhua]

Billionaire investor Warren Buffett said Tuesday that he is more confident in Chinese electric carmaker BYD following his visit.

He said the support to BYD is not for a company or an industry, but for a cause which can make people's lives become more beautiful.

Buffett, together with Microsoft founder Bill Gates, were shown around the company by Wang Chuanfu, Chairman and President of BYD Company Limited.

Buffet came to Shenzhen for the celebration of BYD's 1 millionth car coming off the production line Monday along with the first group of BYD E6s to travel 600,000 km.

Buffett is also due to attend BYD events in Beijing and then in the central Chinese city of Changsha.

Buffett's visit came amid market rumors suggesting he might reduce his stake in the Chinese carmaker after his investment in BYD had risen six-fold.

Buffett's Berkshire Hathaway Group bought 10 percent of Hong Kong-listed BYD, which stands for Build Your Dreams, for $230 million two years ago. That stake is now worth as much as $1.7 billion.

BYD issued a statement Saturday saying reports of Buffett's possible stake reduction were not true.