At least six people have died of AIDS after evangelical churches in Britain told them that God had cured their HIV and that they could stop taking medication, according to a Sky News investigation.

Sky News sent three undercover reporters to the Synagogue Church of All Nations (SCOAN) in London. The reporters told pastors there that they had come to be cured of HIV, and they were told that the church's prayer services were 100 percent effective.

Similar practices were found at churches in Birmingham, Glasgow and Manchester.

A pastor at a church in north London told me I'd been healed, an HIV-positive man, Emmanuel, told Sky News. [He said], 'You've got to stop taking the medicine now. I'll keep praying for you. Once God forgives you, then the disease will definitely go.'

People who come to SCOAN to be cured have to bring a doctor's letter as proof that they are HIV-positive, and they are required to film before and after testimonials to be posted on the church's Web site. According to one of the undercover reporters, Shatila, who is actually HIV-positive, the pastors went over a series of questions with her before the testimonial was filmed and told her how to respond.

The healing procedure itself resembles an exorcism: a pastor sprays water in the person's face and shouts over them.

I was told if I had faith, everything would be fine, and because of my faith, I would be cured of HIV, Shatila wrote. All I needed was to believe that the HIV in my body would go away.

The pastors told Shatila that she would know she had been cured because after you have been prayed for and anointed with holy water during the special Sunday service, you will experience some pains in your body or pass urine more frequently or have some diarrhea. This, they said, means the HIV is coming out of your body.

We've had people come back before saying, 'Oh, I'm not healed. The diarrhea I had when I had HIV, I've got it again, Rachel Holmes, a pastor at SCOAN, said. I have to stop them and say, 'No, please, you are free.'

But diarrhea, pain and frequent urination are actually symptoms of HIV, and if they appear after a patient has gone off his or her medication -- as many people do because they think they have been cured -- it is a sign that their health is deteriorating.

In talking to British doctors, Sky News found that at least six people had died of HIV after their churches told them they were cured. Many churches, including SCOAN, also tell people that they can feel free to have unprotected sex and start a family -- and some have infected their partners with HIV as a result.

I think I've passed it on. He got ill. Physically, he's lost some bit of weight, Emmanuel said. I think he's worried. ... If I'm the one who passed it onto him, I'm feeling guilty. Yeah, very much guilty.

The British Department of Health denounced the churches' healing practices. Our advice is clear that faith and prayer are not a substitute for any form of treatment, especially for HIV treatment, it said in a statement.

SCOAN officials issued their own statement on the investigation: We are not the healer -- God is the healer. Never a sickness God cannot heal. Never a disease God cannot cure. Never a burden God cannot bear. Never a problem God cannot solve. To his power, nothing is impossible. We have not done anything to bring about healing, deliverance or prosperity. If somebody is healed, it is God who heals.

The pastors at SCOAN claim they do not tell anyone to stop their HIV treatments.

We don't ask people to stop taking medication, the church said in its statement. Doctors treat; God heals. Medical doctors do their work, just as ministers of God do. ... There is nothing bad in using medication. It was the same medication that sustained these people before they came to the church. However, they believed that God is the God of nature.

But many churches, like Emmanuel's, do tell people to stop taking medication -- and that poses a very serious public health risk.

It is bad advice, it is foolish advice and it is tragic advice, Lord Fowler, a former British health secretary who led the country's HIV/AIDS awareness efforts in the 1980s, told Sky News. The consequences of this kind of advice can only be that people pass on HIV and can only be seriously bad for the individual concerned -- including death.