Green’s Dictionary of Slang

a gang of pickpockets.

1853

Chester Chron. 25 June 6/6: ‘Busmobs’[...] are accompanied by lads called ‘Wires,’ whose peculiar avocation it is to pick as many pockets as they can and ‘to pass’ the ‘draws’ to the ‘busmobs’ who have capacious pockets for storing away the spoil.