Offenders could face criminal punishment, report Hu Yongqi, Duan Yan and Wang Yan in Beijing.

A crowd gathered to watch on Nongzhan Bridge in Beijing's Chaoyang district as traffic police began their largest crackdown on drivers who drink.

A police sign placed on the road was emphatic: "Please obey command to be checked," as vehicles were diverted to a two-lane area so that drivers could undergo breathalyzer tests.

Police conduct random breathalyzer tests on Beijing's Second Ring Road on May 5, 2011. [Photo/China Daily]

Ma Deqiang, who is in his 40s, suddenly got out of a car and rushed up to police officers. His driver had passed the test, showing no alcohol, but Ma said he wanted to know his alcohol level.

Ma said he had drunk one bottle of beer and 3 liang (150 grams) of white spirits half an hour earlier and had asked his driver to take him home.

The test showed that his alcohol level was 89 milligrams for each 100 milliliters of blood.

According to the newly amended Road Traffic Safety Law, Ma could have been arrested if he had been driving.

"I don't drink and drive. If I have to drink on a business dinner, my driver goes with me," said Ma, who has been running an information technology business in Beijing for about 10 years. "There have been so many catastrophic accidents caused by alcohol. People should ... be much more careful about driving after drinking."

Police officers at checkpoints in Beijing on Thursday night were equipped with video recorders, tear gas and handcuffs. The nail strips are designed to puncture the tires of a fleeing car. Wang Zhenlong for China Daily

Under Chinese law, a driver with 20 mg of alcohol for 100 ml of blood is considered to be drunk. That has not changed. But as of May 1, the penalties became much harsher. Now, for the first time, a driver who registers more than 80 mg for 100 ml is subject to criminal punishment.