ABOUT 450 car passengers found not wearing seat belts were fined 50 yuan (US$7) on Saturday — the first day the new traffic law in Shanghai came into force —Shanghai traffic police said.

At Wujiaochang, Yangpu District, police discovered more than a dozen passengers sitting in the back and not wearing seat belts over a 90-minute period on Saturday morning. Traffic police in suburban Songjiang District said at the weekend it was a “common” occurrence to find back-seat passengers were unaware of the new rule.

Another new rule requiring children under four to be seated in a safety seat when driven also caught some unprepared.

A police officer in Yangpu told Shanghai Daily that traffic police would not ask for evidence of a child’s age from adults in the car and would only issue a fine if it was obvious the child was under four, “such as being held in the arms.”

The new law also imposes a 200 yuan fine and two demerits on driving licenses for those who making or receiving telephone calls or browsing digital devices.

Yesterday morning, police in Pudong discovered four drivers checking WeChat messages or in cases of taxi drivers, checking mobile apps for orders.

A Pudong traffic police officer said drivers using one hand to touch screens of mobile devices were also considered to be offenders.

Up till 3pm on Saturday, police around the city discovered more than 20,000 traffic offenses, a 10.6 percent rise from March 25 last year, according to Shanghai traffic police.

Among the offenders were 116 changing two or more lanes at a time — another of the new offenses stipulated in the law. Those caught were fined 200 yuan. The offense is rampant on elevated roads and expressways.