Should I call child protective services/the cops?

There is a girl on my Facebook who has been stripping since she was 15. She's 16 now. She posts nearly naked pictures and she let's her clients at the strip club finger her for extra money. What should I do? I know for a fact that she works at the strip club.

Edit: I know it's true because she has admitted to it several times. Plenty of underage girls work at strip clubs. it's sad but it happens a lot in my city.