USB redirection in Windows server 2012

I was wondering if USB redirection in Windows Server 2012 could support concurrent users.

I mean, for instance, two users A and B are logged-in a same remote WS server 2012, and user A plugged in a USB key into his ThinClient and enabled the redirection, is there any possibility that user A could find this USB key and do some operations with this USB key?

Please offer me some clue BTW.

thanks.