Dongfeng Automobile Co., a Shanghai-listed maker of light trucks and diesel engines, said Thursday its net profit in the first quarter fell 31.8 percent from a year earlier amid a slump in China's heavy-duty truck market.

Net profit in the first quarter fell to 99.8 million yuan (US$12.48 million) from 146.4 million yuan in the same period last year. Core revenue rose to 2.51 billion yuan from 2.13 billion yuan. Its vehicle sales in the first quarter rose 27.2 percent from a year earlier to 31,243 units, but its engine sales fell 37.2 percent to 21,821 units, Dongfeng said in its earning statement. The slump in China's heavy-duty truck market resulted in sluggish sales at Dongfeng Auto's 50-50 diesel engine joint venture with U.S. company Cummins Inc., the company said.