A teenager is facing prosecution for using the word "cult" to describe the Church of Scientology.

The unnamed 15-year-old was served the summons by City of London police when he took part in a peaceful demonstration opposite the London headquarters of the controversial religion.

Officers confiscated a placard with the word "cult" on it from the youth, who is under 18, and a case file has been sent to the Crown Prosecution Service.

A date has not yet been set for him to appear in court.

The decision to issue the summons has angered human rights activists and support groups for the victims of cults.

The incident happened during a protest against the Church of Scientology on May 10. Demonstrators from the anti-Scientology group, Anonymous, who were outside the church's £23m headquarters near St Paul's cathedral, were banned by police from describing Scientology as a cult by police because it was "abusive and insulting".