GeenStijl puts it all in a nice summary (NL):
Of all youth in the Netherlands, around 14% come into contact with the judicial system. Of Dutch males, 20% runs afoul of the law, in Moroccan males this is 54%. Morroccan youth are also the youngest when they first commit crime and on average are charged 4.1 times.So, can we, from this point on, admit there is a problem WITHOUT immediately be labelled a backward, racist troglodyte?
Turkish males commit mostly violence, while Moroccans commit property and financial crime. Ethnic Dutch are mostly caught vandalizing, for disorderly conduct in public or for traffic offences.
Of Dutch girls 4.5% comes into contact with the justice system, of Moroccan girls this is 16.6%.
Among habitual criminals there are 12.8% autochtone Dutch, while 32.3%(!) of them are Moroccan. Moroccan girls are twice as likely to be 'habitual' criminals as are Dutch girls. And lastly: Criminal 'allochtones' are more violent then criminal 'autochtones'.
[Instant Update] And before anybody brings up that lame old excuse: No, there is no statistically relevant relation between crime and socio-economic factors in the Netherlands (pdf; NL).