SHENZHEN -?Shenzhen police said on Friday they have detained 140 suspects in a social media fraud scheme.

Police mounted four operations from May 5 to 12 in Dongguan City and Shenzhen to nab the suspects, who allegedly used social media to commit fraud, Shenzhen police said in a statement.

The suspects, organized as a pyramid scheme, registered WeChat and QQ accounts, sought male victims and swindled their money, it said.

The sum of money taken from the victims has not yet been published. According to police documents, a victim, surnamed Liu, was cheated out of 8,000 yuan (about 1,200 U.S. dollars) after he befriended a stranger through the "shake your phone" function on WeChat.

Liu became emotionally involved with the purported female friend, who later borrowed money but soon disappeared.

Further investigation is under way.