Goldblog is excited about this story:

When hate crimes strike the Dutch capital, the police officers head to the costume store. Amsterdam's law enforcement regularly disguises themselves as members of a persecuted faction, patrols the streets incognito, and then arrests any violent perpetrators they encounter. In response to a spike in muggings, officers posed as pensioners and "grannies"; to combat harassment of the homosexual community, officers of the same sex acted affectionate in public. Now Dutch police will go undercover again -- this time with the earlocks and black top-hats of ultra-orthodox Jews.

I once saw a parody of an Arnold Schwarzenneger movie about something like this: