Police in Zhangzhou city busted a pyramid scheme and saved 14 trapped workers last Friday, Strait News reported.

Key to the raid were some one-yuan notes and tissues discovered at a community in Shangcheng town. Each was marked with SOS messages suggesting the existence of the ring.

Police searched for the origin of the messages and found a woodshed with one woman and 13 men confined inside, all of whom were swindled by the illegal ring.

The writing of SOS messages on notes and tissues was suggested by Shu Kang from Southwest China's Guizhou province, one of the trapped workers.

"All of our belongings were taken away, with only a few pens, tissues and one-yuan bills left. Then it occurred to me that maybe that would help. But I am still surprised that someone believed what we wrote and was kind enough to call police for us," he said.

The banknotes and tissue bearing SOS message written by workers trapped by a pyramid scheme ring in Zhangzhou city, Fujian province. They read, from left, "Please call 110 for me!" "Someone please help me!" "I’m begging you to call police!"