Four people have been arrested for organizing a paid blood drive involving 17 donors, metro police said Thursday.
Police said five suspects, one of whom is still at large, earned 5,000 yuan ($814) by recruiting unemployed people to donate blood, according to the metro police.
"They were more like blood scalpers, who sold their donors' blood to companies who needed to meet group donation quotas," said Zhou Wei, a press officer with the Shanghai Public Security Bureau's metro police division.
Though China's Blood Donation Act forbids compensation for blood donors, many schools, companies and organizations offer donors cash and other compensation to encourage donations.
One middle school teacher surnamed Liu told the Global Times that at her school, teachers were each paid more than 2,000 yuan to donate blood.
Most companies and universities have to meet blood donation quota every year, and blood scalpers can help fill the gap when they fall short.
Zhou said the blood scalpers pay their donors, but still charge their buyers enough to make a profit.
Police did not disclose how much the suspects earned from each donation.
The gang caught police's attention in March when a metro police officer stumbled upon two young men quarreling at Hongqiao Road Station on metro Line 3.
Police found that one of the men had refused to pay the other the 300 yuan that he promised for the other's blood donation. The donor was angry and had followed the scalper all the way to subway station, demanding his money.
The scalper, surnamed He, admitted that he and other three suspects looked for unemployed people to sell their blood. Police later found six donors who helped identify the suspects.
A person who organizes a paid blood drive can face up to five years in prison, according to China's Criminal Law.
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