The number of drunken driving cases has dropped dramatically in China since May 1, 2011, when an amended law that imposes harsher punishment on drunken drivers took effect, according to the Ministry of Public Security.

Over the past two years, police have handled 871,000 cases of driving under the influence of alcohol, down 39.3 percent compared with the same period from 2009 to 2011, the traffic management bureau under the ministry said on Wednesday.

Of those, 122,000 were drunken driving cases, a drop of 42.7 percent from 2009 to 2011, according to the bureau.