Detective Chief Inspector Dave Whellams said it had been a "serious, horrible offence which required a degree of planning and calculation":
Mary Konye has had to purchase, at some point, some sulphuric acid. She has prepared for this over a number of months, even years, all resulting from a trivial, insignificant argument that everybody has in their everyday lives.
But Mary Konye has taken this so far that she has planned this, disguised herself and followed Naomi on that night of December 29 2012.
The result today will give Naomi only some comfort but she is never going to be away from the fact that she is scarred, every time she looks in the mirror she is going to be reminded of the fact but it will enable her to start to get some closure.
She is a very brave woman and one I have great sympathy for.
More top news
Clear tonight with temperatures falling quickly. Light winds and lows of 5C.
An elderly and vulnerable man is fighting for his life after being mugged while riding a mobility scooter.
The latest disruption on an increasingly delay-affected Underground system was on the Central line.