The chemical is the same explosive that was used by the terrorists responsible for the London bombings in July 2005 and by so-called shoe bomber Richard Reid, who tried to bring down American Airlines Flight 63.

When arrested by police, the teenager said he had bought the chemicals from local hardware stores and pharmacies and made the bomb out of curiosity.

Magistrate Denis Lau adjourned the hearing until Oct 15, granting the teenager bail to allow for the preparation of psychological and psychiatric reports.