"It is believed more than a million drivers have been trapped by the system.
But it is now claimed the lights were rigged to change from yellow to red in three seconds instead of the regulation five or six seconds.
The fraud was uncovered by a senior police officer who noticed an unusually high number of fines being issued.
Instead of an average 15 fines a day in some places, the figure jumped to more than 1,000.
The fraud may have netted as much as $170m (£116.4m) for those involved."