It was very worrying to read about the policeman who was a gang member and led a double life under the nose of the Singapore Police Force (Cop jailed one year for being gang member; June 21).

What is disturbing is that the police force which is tasked to be crime-busters, had overlooked failed to detect a black sheep within their fold.

Surely there would have been telltale signs over the years.

If these were not picked up on, then it is time the police force relook how they perform security checks on their long-time staff serving in the force.

My worry is that there are others like him still within the force who have not been detected.

Florence Veronica Minjoot (Ms)