WUXI, Jiangsu -- Vehicle emissions are the top pollutant in Beijing, vice minister of environmental protection Wu Xiaoqing said here Wednesday.

Motor vehicles are also the primary source of pollution in Guangzhou, Hangzhou and Shenzhen, Wu said at an environment conference, citing an analysis of pollution sources in nine major Chinese cities.

China had 264 million motor vehicles on roads as of the end of last year, including 154 million automobiles, next only to the United States. There are about 5.6 million motor vehicles in Beijing, with an average of63 cars among 100 households.

The analysis is aimed at helping authorities customize measures for air pollution control, according to Wu.

Shanghai, Tianjin and Ningbo's top pollutants are dust and industrial emissions, while Shijiazhuang and Nanjing's top pollutants derive from coal burning, the analysis report showed.

Wu said China will complete the pollution source analysis for 26 major cities within this year.