Dong Hui/Shanghai Daily news

A total of 23 trucks which were overloaded or had illegally dumped construction waste were caught by Hongkou District police over the past two months, the district's public security authority said.

"More than 200 tons of cinders and ash were randomly dumped in Hongkou District each day on average before the intense action," said Chen Xuankai, media coordinator with the district police. "Now the figure has dropped to about 20 to 30 tons, a clear decrease."