China's State-owned vehicle manufacturer Beijing Automotive Group Co Ltd said on Wednesday it had agreed to buy smaller domestic firm Zhenjiang Automobile to help it meet its target to double production by the end of 2015. Beijing Auto did not disclose the value of the deal but said in a statement it would invest 15 billion yuan ($2.45 billion) in Zhenjiang Automobile to expand vehicle production. Beijing Auto aims to produce 3.5 million vehicles by the end of 2015, compared with 1.7 million last year.