CHENGDU/BEIJING, July 20 (Xinhua) -- Four years into China's reform on government car use, the private use of such vehicles has been almost stamped out across the country.

Like other government officials in southwest China's Sichuan Province, Zhang Li drives a marked government car to work.

An oval containing the words "government car" is sprayed-painted on the car's front doors. It also includes a phone number the public can call to report any misuse of the car.

"The use of official cars has become more standardized in the past two years," said Zhang. "All of them have been clearly marked. Anyone can tell if it is an official car by a simple glance."

Statistics show nearly 10,000 government vehicles in Sichuan have been marked, enabling the public to monitor their use.

All 80,000 official vehicles in the capital Beijing have also been marked with stickers on their windshields, according to local authorities.

China's central government released a guideline in 2014 to reform the use of government vehicles, in an effort to cut hefty spending and curb graft amid mounting public complaints about the private use of official vehicles.

According to the guideline, all government vehicles should be marked with obvious signs, except those used for special services, such as police investigations and national security.

All 31 provinces, municipalities, and autonomous regions on the Chinese mainland have started marking government vehicles. The vehicles are either spray-painted with signs on their bodies or marked with stickers on windshields.

"The signs are so obvious that the officials are always under public supervision," said Wang Yuanping from the People's Procuratorate of Fucheng District in Mianyang, Sichuan.

Signs on government vehicles have been very effective in solving the long-standing problem of official vehicles being used for private purposes, said Wang Yukai, with China Society of Administrative Reform.

In addition to public supervision, local governments have also started applying high technology to oversee the use of government vehicles.

The Beidou navigation system, a global satellite navigation system, has been installed in all the government cars in Beijing to ensure they are used strictly for official purposes. Any use during non-working hours or in non-permitted areas will lead to an automatic alarm that will be put on record.

Big data analysis has also been adopted to monitor any unreported use of government cars running on highways during holidays. In just five minutes, all the government cars in Beijing were screened during the National Day holiday last year.

"One must be out of their mind now to even think about visiting tourist spots in government cars," Wang added.