Police are urging residents not to view the contents of mysterious CDs that are being distributed in Borehamwood.
Police are investigating the content - believed to be violent and indecent images - on a number of CDs found in the area and printed with Hebrew writing that says "the lord, Hallelujah".
Inspector Richard Vine, of the Chiltern and South Bucks Neighbourhood North Policing Team based at Amersham, urged residents not to open the CDs on their computers.
He said: “I would like to reassure the local community that we are investigating this and I would urge anyone who receives, or finds, one of these discs not to open them on their computer or laptop, but to contact us via the 24-hour enquiry centre on 101.
“I would also like to appeal for anyone who saw these discs being distributed, or has any further information, to get in touch and assist us with our investigation.”
To give information anonymously, contact Crimestoppers on 0800 555 111.