sandbagger

1. (historical) A robber who sandbags (suddenly strikes, with a sandbag or other object, so as to stun) victims.Examples: "The Day-Globe, Waco, Texas, July 5th., 1893, writing on "The Conscienceless Juror," says: […] 'Red Farrel' a notorious sandbagger and robber was on trial in Judge Moise's Court."; "The American sandbagger, like so many others (including the mugger), evoked the street robber's violent technique. It was from sandbag, to ambush or hit without warning: whether an actual sandbag ever entered the picture was irrelevant."historical