Police are investigating an email chain-letter containing pictures of mutilated bodies and threatening death if the receiver does not pass it on.
The email, a graphic version of threatening chain-letters, was sent to a Christchurch child and is now under investigation by police and the Department of InternalAffairs.
A Christchurch father has told investigators it took two hours to calm his 12-year-old son after he saw close-up colour photographs of mutilated bodies.
The email asks children to forward it to 10 people or they will end up like the bodies.
The email had been forwarded by a friend in a nearby city.
The images are linked to an American website that contains photographs depicting violence, death and sex.
The direct link to the site seems to allow the email to bypass many filtering systems.
Internet Safety Group director Liz Butterfield, who was contacted by the concerned parent, said she was worried that children would believe the threats and pass the email on in fear.
Ms Butterfield said it was a "sickening twist" on chain-letters, which also threatened recipients with death if they did not pass them on.
The email is believed to be sent to Hotmail accounts and is targeted at youngsters because it uses simple language and cellphone text-messaging terms.
The subject header usually contains "This will really make you ill" or "This is dirty".
Ms Butterfield urged children to delete the email if they saw such words. "Don't pass it on to friends as it is not a joke."
Chief Censor Bill Hastings labelled the photographs as objectionable material. He said the email probably originated from overseas, making it impossible for police to prosecute.
But anyone in New Zealand spreading the email could be fined a maximum of $20,000 and jailed for up to a year.
Parents are asked to ring the Internet Safety Group, toll-free on 0508 638-723, if they see the email.
