WASHINGTON—The calculator used by the Virginia Tech student killer is up for sale on the Internet along with a lock of hair snipped from notorious assassin Charles Manson and letters from several serial killers.

The market for buying grisly souvenirs linked to infamous crimes is growing in the United States, with a half-dozen websites sharing what is dubbed the “murderabilia” industry.

Gruesome mementos

Other gruesome mementos include copies of court pleadings, signed photos and even items from people who were accused of being involved in cannibalism.

For $3,700, Supernaught.com is selling a calculator that it says “was one of the few items that the Virginia killer Seung-hui Cho sold on eBay to raise money for the guns, clips and ammo utilized during the rampage.”

Cho, 23, went on the rampage on the campus of Virginia Tech University in 2007 gunning down 32 people before killing himself in the nation’s worst ever school massacre.

An X-ray of Manson’s spinal cord is for sale for $8,500. Supernaught.com claims to have received it from someone “very close to Manson” who obtained it from an employee of the prison where one of the world’s most famous criminals is serving a life sentence.

The X-ray is among several items from the leader of the “Family” that orchestrated the 1969 brutal murder of actress Sharon Tate, wife of filmmaker Roman Polanski. She was 26 years and 8-1/2 months pregnant when she was killed.

“Manson items are always in high demand,” Eric Gein, owner of serialkillersink.net, told AFP. “After all, Manson is the 20th century ‘bogeyman.’ Any collector worth his salt owns at least one item from Charles Manson.”

Serialkillersink.net’s product line includes signed photographs and letters from Manson.

‘Everyone’ buys

The “market is booming,” says Gein, who has sold more than 500 items in three years, thanks in part to indirect advertising via reports in the US media about murderabilia sites.

“Throughout history there has been a desire to own objects related to infamous crimes,” he said, citing Roman soldiers who took fragments of Jesus Christ’s crucifix and collectors of Nazi insignia.

In 2011, even the US government auctioned personal belongings of “Unabomber” Theodore Kaczynski, who was sentenced to life imprisonment in 1998 for killing three people and injuring 29 by sending them letter bombs, Gein said.

In order to obtain items, “we have gotten to know most well-known serial killers on a personal level,” Gein says.

Many of the items “are sent from the inmates from their prison cells,” he said, giving assurances they were not paid.

Digest of US criminal history

Murderauction.com, an auction site, is another digest of American criminal history, offering to sell a letter from Mafia boss Al Capone (starting price $8,000), pictures of Wild West bandits ($10) and bags of soil used to bury serial killers’ victims.

The objects “come from a number of places… prison museums, prison hobbycraft gift shops, correctional officers will steal items from inmates and sell them, but most often they are simply mailed out by the inmates,” said William Harder, who manages Murderauction.

As for customers, “it’s everybody,” he told Agence France-Presse, “lawyers, cops, construction workers, doctors, you name it, I’ve sold to them.”

For the families of victims, the trade in crime memorabilia can be nauseous.

“What type of sick individual would want to make a profit off of showing my dead baby?” asked Pam Hobbs, who recently was interviewed by WMC-TV in Memphis after photographs of the bodies of three of eight murdered boys were sold, including one that showed her son.

Heinous industry

Eight states prohibit sales of crime memorabilia. Campaigns have been launched to ban what Republican Senator John Cornyn of Texas called “this heinous industry”. He authored a bill last year that would ban the sales.

The merchants are more concerned about government intervention into private business.

“The United States was based on free enterprise,” Harder said. “I have the right in this country to sell whatever I wish.”

Gein added: “We do not solicit anyone. People come to us with an interest in purchasing true crime memorabilia. For those who are offended by what we do, they simply do not have to visit the website.”