"I would like to express my sadness and distress on hearing of the death of assistant referee Richard Nieuwenhuizen," wrote Blatter in a letter to the Dutch football association.
"I was deeply shocked to learn of this tragic incident. Football is a mirror of society, and sadly the same ills that afflict society - in this case violence - also manifest themselves in our game.
"Nevertheless, I remain convinced that football, through the example set by the tireless efforts of people like Mr. Nieuwenhuizen, is a force for good.
"We must continue to use its positive example to educate people against these wrongs."
The three culprits, two aged 15 and one 16, will stand trial after they are charged with 'manslaughter, assault or public violence'.