Police are hunting the supplier who gave far right fanatic Thomas Mair the gun he used to murder MP Jo Cox.
Mair, 53, was given a whole life jail term yesterday for killing the Batley and Spen MP in June.
He repeatedly shot and stabbed the 41-year-old mother of two.
The .22 rimfire weapon, which had been cut down so it could be fired one-handed, was stolen a year before the killing.
Mair is thought to have got hold of it within weeks of the murder.Det Supt Nick Wallen, who drove the examination, said: "How he, a withdrawn recluse with no past criminal history, no criminal ring of people around him, how he came to be in control of that weapon is especially a dynamic line of request."