How can I remove black spray paint stains from concrete?

It will be very difficult with the methods listed thus far. A sand blaster will be needed to do a nice job.How can I remove black spray paint stains from concrete?
The above remedies should work well. However, if you are removing 'tagging or gang graffiti', I would just paint over it, because it is likely to reappear. If this is the case, make sure you document it (pictures) and alert your local police before removing/covering it.How can I remove black spray paint stains from concrete?
goof off is good but the fumes will about knock you out. Very strong.
possibly a pressure washer would work. they can be rented, like at United Rentals.
Try ';Goof Off'; It is to remove grafetti.
just get some paint stripper
Try some warm water and detergent. Mix the two and then apply with some sand paper (coarse stuff) 80 to 120 gritt