They're looking for a guy in his 40s with a receding hairline who robbed a Northern Trust Bank on Brickell Avenue this afternoon.
He didn't make it far before a dye pack exploded inside the bag of cash a teller handed him. The robber ditched the money that got stained red and took the rest with him, police said. Investigators suspect some of the red dye may have gotten onto the robber as well.
Dye packs are pretty nifty devices -- here's an article about how they work.