Police Commissioners have urged the Met Police to add ultraviolet dye to their three water cannon to help them track down any one responsible for violent protests.
The Deputy Mayor for Policing and Crime, Stephen Greenhalgh, told the London Assembly today that Commissioners around the UK backed the use of "SmartWater", which is currently used to identify shoplifters and burglars.
Stephen Greenhalgh said:
Recently, London mayor Boris Johnson agreed to be blasted by water cannon after his controversial decision to buy the weapons for Scotland Yard.
Earlier ths month, the Mayor's Office confirmed Boris Johnson authorised the highly-controversial purchase of water cannon - despite not yet getting the go-ahead from the Home Secretary.