The US Federal Trade Commission (FTC) has shut down four illegal email spamming operations, including one that offered the opportunity to "date lonely wives."

Two of the operations sent spam that hijacked the computers of third parties, and used them to spam customers with sexually explicit email, said the FTC. The four operators were charged with violating the CAN-SPAM Act and courts in Illinois and Arizona approved the FTC's request to shut the operations down.

Cleverlink Trading and its partners will give up $400,000 in spam-related gains to settle the FTC charges that email from them violated federal law. The FTC sued the group, saying their "date lonely wives" spam violated nearly every provision of the CAN-SPAM Act.

Cleverlink's email contained misleading headers and deceptive subject lines, it did not contain a link to allow consumers to opt out of receiving future spam, did not contain a valid physical postal address and did not contain the disclosure that it was sexually explicit, the FTC said.

It also included sexual materials in the initially viewable area of the email, in violation of the FTC’s adult labelling rule.

In a second case, the FTC charged that Zachary Kinion sent spam hawking adult sites, mortgage rates and privacy software, and paid other spammers commissions to send spam messages for him. Kinion hid his true originating address by routing his spam through the computers of innocent third parties.

An Illinois court ordered him to halt operations. A settlement, which the FTC agreed to in June, includes a judgment of $151,000, suspended because of Kinion's inability to pay.

A third operation used "spam zombies" - computers used without their owners’ knowledge - to conceal the source of sexually explicit spam. Defendants William Dugger, Angelina Johnson and John Vitale also violated the adult labelling rule, the FTC said.

A settlement, approved in Arizona, requires the three defendants to give up $8,000 in spam-related profits, and it requires them to obtain permission from other people's computers before using them to send email.

The fourth operation used spam to drive traffic to websites, the FTC said. Brian McMullen, doing business as BM Entertainment and B Pimp, routed his promotions for pharmaceuticals and adult content through unwitting consumers’ computers, the FTC said.

A settlement approved by the Illinois court in July imposes a judgment of $24,193, suspended based on McMullen's inability to pay, the FTC said. In addition, he has pleaded guilty to criminal charges related to spam and unauthorised possession of credit cards. He currently is awaiting sentencing.