A national amnesty for owners of a revolver commonly used as a starting gun has come to an end.

On Friday, the Olympic .380 BBM firearm was reclassified as a prohibited weapon, following fears it could be easily converted to carry live ammunition.

The gun is most commonly used to start races and to train dogs, and has traditionally been available from hobby and model shops as well as firearms dealers.

However, a test carried out by the UK's Forensic Science Service in February found the pistol could be altered to make it a lethally barelled weapon and in April, an amnesty was launched to allow owners to get rid of their guns before they were made illegal.

On Friday, that amnesty ended, meaning anyone still in posession of the gun could now face prosecution.

Assistant Chief Constable George Hamilton from the Association of Chief Police Officers in Scotland said: "We are aware that many individuals may have purchased the Olympic .380 BBM for well established legitimate uses and we have been working with athletic associations, suppliers and other groups who commonly use the revolver, to advise them of the change in status.

"From June 4, anyone found in possession of an Olympic .380 BBM risks prosecution and a prison sentence of up to five years."