When Britain was fighting for her very life during the Second World War the Home Guard, desperate for volunteers, recruited immature boys of 16 and 17. This was something of a poisoned chalice, for the boys tended to ape the older men with whom they came into contact.

Instead of the motor bikes and computers beloved of today’s teenagers, they had guns and live ammunition to play with. In Cardiff, off duty from the Home Guard, they formed armed gangs which became sometimes as much a nuisance to the war-weary citizens as the enemy overseas.

On the night of Thursday, December 11th, 1941, Police Sergeant Herbert Lilwall and Constable Evan Davies were called to an air raid shelter in Whitchurch Road where, according to complaints from residents, armed teenagers were up to no good.

Davies went into the shelter and Lilwall went off to North Road to deal with another gang. In the shelter Davies confronted five youths. No one knows exactly what happened next. A gun fell from someone’s mackintosh, two shots were fired, and the gang rushed for the exit, leaving the constable crumpled on the concrete floor. The shots had ploughed through his heart and he died almost instantly.

One of the runaway youths was believed to be Lyn Evans who was found shot in the head in a field near his home five days later. His death was thought to be accidental.

When an inventory was taken at the local Home Guard store a sub-machine-gun, an automatic pistol and 400 rounds of ammunition were missing. But as the police rounded up the local teenagers, they recovered 12 automatic pistols and revolvers and cleared up nearly 50 cases of burglary and housebreaking.

The youth who fired the shots that killed Constable Davies – who has the unfortunate distinction of being the last police officer killed on duty in Wales – was never identified.