A charity has urged Scottish teachers to be cautious about who they invite to speak to students after discovering that an anti-drugs group has links to the Church of Scientology.
The Marathon for a Drug-Free UK event began in Brighton on 26 April and is due to finish in Edinburgh on Wednesday. It involves anti-drugs campaigners running from Brighton to Edinburgh and giving talks to schools along the way.
Those taking part will encourage children to sign "drug-free pledges" and distribute a booklet entitled The Truth About Drugs.
But charity Mentor UK, which runs programmes to protect children from alcohol and drugs in Scotland, says the organisation fails to make explicit its links to the Church of Scientology. Mentor UK has also accused it of using "scare tactics" and "inaccurate information" to turn young people off drugs - an approach it claims could be counterproductive.
"We are concerned that some of the information provided does not meet the high standards of accuracy we would wish to see," a spokesman said.
The materials relate the experience of someone who takes ecstasy, with the effect of making her "crazy", biting a glass and tearing rags with her teeth.
Ian Haworth, founder of the Cult Information Centre in London, warned schools not to be "trusting and naive" and always to vet the backgrounds of groups and individuals offering to give talks.
"Groups about whom we are concerned are constantly trying to give a good impression either to get you to come through their door or get through your door," he said.
Mandeep Birdy, a spokesperson for Marathon for a Drug-Free UK, stressed that the marathon was "a non-religious activity" but admitted that the Church of Scientology had "kindly donated money" for the drug education booklets.
He continued: "We have found the information in the Truth About Drugs booklets to be very accurate and effective, giving just the facts about drugs along with not 'scare stories' but real-life stories from former drug users."