The ten strong Romanian gang all pleaded guilty to the offences between December 2012 and February 2013 and were sentenced at the Old Bailey for stealing more than a million pounds worth of jewellery.
The court heard how the Flying Squad at Barking launched an investigation - code-named Operation Tiburon, following a spate of well planned and executed robberies in Wembley, Ilford, East Ham, Southwark and Haringey.
The gang targeted Asian jewellers stealing mostly 22 carat gold items. Their modus operandi involved the group forcing entry into the premises using an array of weapons including hammers, axes and sledgehammers, often using violence to frighten members of staff within the shops.
Fleeing the scene once they had amassed large hauls of valuable items, the gang on a number of occasions escaped via nearby railway lines, discarding identifiable items of clothing and secreting the stolen items in pre-dug holes.