Authorities in China have arrested four people in the city of Xi\u2019an in connection with a suspected cryptocurrency pyramid scam, according to local media reports. The arrests were made over allegations that the scheme had conned some 13,000 individuals, with a total of over 86 million yen ($13 million) reported to have been collected. Police arrested a primary suspect, along with three others suspected of assisting in the scheme. The suspect, known only at this stage as Zheng, is said to have begun planning the scam back in October 2017. Police suspect the scam revolved around the Da Tang Coin (DTC), an altcoin linked to a company called DTC Holding. Investigators said the scheme involved offering investors a guaranteed return of approximately $13,000 per day, in return for an investment of $480,000 in DTC\u2014which were offered at $0.50 per coin. The scam allegedly attracted significant volumes of investment in the space of just two weeks, from March 15-28, with the company reaching out to investors in locations including Xi'an, Ningbo and Phnom Penh. It is also alleged that the firm secured the services of a \u2018foreign-looking\u2019 man in order to create the appearance of an international blockchain startup that is heavily backed by other investors. Investors were promised a return on their money when DTC was ultimately listed on major cryptocurrency exchanges, and were told of a range of real-life applications for the token, including in retail and education. While labelled a pyramid scheme by investigating officers, some analysts have highlighted that the plan more closely resembles a Ponzi scam. Either way, officers believe the men to have been involved in the latest cryptocurrency scam to target unsuspecting investors. In 2017 alone, China reported some 47,000 victims of cryptocurrency scams, like the alleged scam in the present case. Around 40 arrests have been made to date, leading to the Ministry of Public Security promising to \u2018purify cyberspace\u2019 to protect victims. The pledge comes in light of a wider crackdown in China, with authorities keen to prevent scams of this kind from taking hold. The arrests this week will do little to dampen the appetite of regulators in keeping a tight grip on cryptocurrency activities in China.