An organisation linked with the Scientology movement have given lectures on drugs awareness at two London schools.

Narconon UK, an organisation that offers drug prevention and rehabilitation programmes, gave talks at the Camden School for Girls and Brecknock Primary School in north London.

The organisation's parent company is the Association for Better Living and Education, which is owned and controlled by the Church of Scientology, the controversial sect denounced as a cult by critics. The sect denies these accusations.

Scientologists believe that humans are haunted by the spirits of aliens brought to Earth in spaceships and massacred with hydrogen bombs by a galactic warlord called Xenu 75 million years ago. Its devotees include Hollywood actors Tom Cruise and John Travolta.

Narconon states its programme is, "based on the research and writings of L Ron Hubbard, the founder of the Scientology religion".

Two pupils attending the discussion told the London Evening Standard they became alarmed when the speaker quoted Hubbard, describing him as a "great humanitarian."

Both schools said they were not aware of the links between Narconon and the Church of Scientology, and that teachers supervised the talks, which were exclusively focused on drugs prevention.

David Touretzky, a professor at Carnegie Mellon University in Pittsburgh and an authority on Scientology and Narconon, told the newspaper: "The first step is to get people to see L Ron Hubbard as a benevolent authority figure instead of a sociopathic cult leader. The drug education programme is just about taking that first step."

Noel Nile, president of Narconon UK, said: "We're in the business of saving lives. The lectures are not concerned with religion."