From the Pittsburgh Police —

There have been several reported bump and run pick pocketing incidents reported to the Pittsburgh Police. In all cases, the victim was bumped into by a well dressed man, who apologized profusely. It was not discovered until later that the victim had their wallet stolen by the man, and had successfully used their credit and debit cards.

If you are the targeted victim of such a scheme, please ensure that your belongings are where they are supposed to be. If something is missing, please call 911 and give a description of the person who bumped into you.
Also, please keep all belongings in your possession and do not walk away from a bag or purse while in a public area like a supermarket or public library.