Dr Jameel Ahmed, Deputy Inspector General (DIG) south zone, said a detonator carrying a very small amount of explosive material was presented to the court on the judge’s request following an application by defence counsel.

The defendant in the case was facing a charge of possessing explosive materials.

It was removed from a glass vessel by a court clerk who subsequently removed a pin from the device to show it to the judge.

But removing the pin caused an explosion which injured ATC Judge Shakeel Haider, the clerk, a policeman and two others who were present in the court.

The sound of the explosion caused concerns about an intentional attack in the courtroom and bomb disposal experts were immediately despatched.

Dr Ahmed said safety measures for presenting explosives in court are now being reviewed.