Cyclist Hit By Chunk Of Concrete
http://minnesota.cbslocal.com/2015/08/09/answers-tough-to-find-after-cyclist-hit-by-chunk-of-concrete/
If you live in Minneapolis watch out and contact the local authorities if you have any information..
I would like to say this is rare but I have seen it in Orlando also. I have had beer bottles thrown at me while cycling AND running. I seen tacks throw onto the road. Car intentionally try to get close to cyclist. At IM Chat they had oil and tacks on put on the road.
Watch out and be careful.