Use of chemical, biological or nuclear weapons

A person who, unlawfully and intentionally uses, threatens or attempts or conspires to use chemical, biological or (a) at any airport, aerodrome or aeronautical facility; or (b) in or within an aircraft, while the aircraft is in flight, in service or parked on the ground, commits an offence and shall be liable, on conviction on indictment, to imprisonment for a period of not less than twenty years.