It's a link to a comment on this subject that says:

Ok, so to explain. This DID happen,literally 500m from my home :) the system was designed to store reg plate numbers and later turned to a speed camera. The stunt was done by a few students of the Technical University, it did bring the whole db down. They tried to revive it, but ultimately the boards have been dead for the past 5 years or so. Mind that this hack was performed around 7 or 8 years ago:) I can provide pics of the dead board now and exact coordinates too:)

And then later in the replies they do give the coordinates of the camera billboard thing they broke, and someone posts a Google Maps screenshot of the board at the coordinates they gave that just looks like a little digital billboard that's turned off and is just black, and the OP confirms that it is the board they mentioned.

Hope that all makes sense; I've got a lot brain fog/stress brain and stuff and it felt like too much to screenshot lol