Officers stop a middle-aged woman at Zhongshan Park Station during a crackdown on fare dodgers Tuesday. The woman was caught using her mother's senior citizen pass to ride for free. Photo: Yang Hui/GT

The Shanghai metro fined 172 passengers Tuesday morning during a crackdown on fare dodging, local media reported.

The metro operator, Shanghai Shentong Metro Group, launched the campaign after microbloggers complained that fare dodging was becoming more prevalent with the approach of the Spring Festival holiday, said Lan Tian, a press officer with the company.

The city's subway system usually experiences an increase in passengers around the holiday, many of whom are migrants on their way back to their hometowns.

Fare dodging is long-standing problem in Shanghai. In 2012, the metro operator caught 202,575 fare dodgers, fining them 476,742 yuan ($76,614), according to a report on the news website eastday.com.

Shanghai Shentong dispatched 40 people posing as passengers Tuesday to stand near the turnstiles and watch for fare dodgers, Lan said. In addition, two metro police officers were posted at each station.

"Most fare dodgers duck under or jump over the turnstiles," Lan told the Global Times. "Some try sharing a single ticket. Some use fake certificates that give certain groups of people the right to ride for free. Others use the free ride passes given to senior citizens."

Tuesday's crackdown, which lasted from 7:30 am to 9 am, targeted stations where fare dodging is most prevalent, including Xinzhuang Station, Zhongshan Park Station and Zhongxing Road Station, according to a press release from the metro operator.

Authorities handed out 4,354 yuan in fines during those 90 minutes, the press release said. They caught 128 people jumping or ducking the turnstiles or sharing tickets, 42 taking advantage of senior citizen passes and two passengers with fake certificates.

Authorities can fine passengers as much as 50 yuan for fare dodging, Lan said.

Passengers caught misusing senior citizen passes can have the passes confiscated for at least 15 days.

The metro operator plans to broaden the campaign to most of the city's metro stations by February 6, especially those where fare dodging is commonplace, such as Shanghai South Railway Station and Shanghai Railway Station, Lan said.

The operator vowed to restart the campaign after the Spring Festival if they see another increase in fare dodging, Lan said.