What just happened? A stir was created online yesterday when users of several applications began to report that New York City was being labeled “Jewtropolis” on in-app maps. Zillow, Snapchat, Citibike, and others were affected.

Ars Technica reports that the problem arose due to an incident of “data vandalism” on the crowd-sourced mapping project OpenStreetMap (OSM). The project is used by many applications including Wikimedia to provide labels, street maps, and GPS traces over area maps. Unfortunately, any time you open something to the public, there are bound to be trolls and mischief makers.

The Jewtropolis label was not the only vandalism that occurred. One user going by MedwedianPresident made changes to several roads, bridges, and tunnels in New York as well. The Manhattan Bridge, for instance, was renamed “Ku Klux Klan Highway,” and the Hugh Carey Tunnel became “Adolf Hitler Memorial Tunnel.” This particular vandal has a record going back 2 years.

However, this type of petty crime on OSM has been going on for much longer than 2 years. In 2010, a vandal created a fake town called "West Harrisburg" and traced GPS routes for non-existent streets over farms and forests.

According to a representative of the OpenStreetMap data working group, the “Jewtropolis” label was not even from current maps.

“The problem that you are seeing was caused by a vandalism [sic] that happened 20 days ago,” said Nelson A. de Oliveira speaking for the group. “It was promptly reverted and fixed, but data consumers which, for some reason, are still using an old copy of OSM data, may still display the wrong result.”

Mapbox, which collects map data from multiple sources, including OSM, and sends it to third-party apps, was the one to push the nearly month-old label that had already reverted. The company issued a statement this morning explaining the its stance on the matter and how the antisemitic slur slipped out.

“[Mapbox has] a zero-tolerance policy against hate speech and any malicious edits to our maps. The malicious edit was made by a source that attempted several other hateful edits. Our security team has confirmed no additional attempts were successful. [Mapbox receives data from 130 sources and] has a strong double validation monitoring system. While our AI immediately flagged this [label], in the manual part of the review process a human error led to this incident. Security experts are working to determine the exact origin of this malicious hate speech. We apologize to customers and users who were exposed to this disgusting attack.”