GUANGZHOU, Dec. 6 (Xinhua) -- A total of 233 telecom fraudsters were returned from Cambodia to southern China's Guangzhou Thursday afternoon.

The suspects are behind more than 2,000 fraud cases across over 20 provincial regions, involving over 63 million yuan (about 9.14 million U.S. dollars), according to the police.

The police said the suspects changed their phone numbers and pretended to be public security, procuratorate or court officers to threaten the victims for money.

Zhao Kezhi, Chinese state councilor and minister of public security, said China had launched a new campaign to further crack down on telecom fraud from December until the end of 2019.

There has been about 31,000 telecom fraud cases filed nationwide since January, a drop of 36.8 percent year-on-year, according to police.