Basic http authentication and remove the prepend text username:password@ from the Static content (i.e image/js/css) url

I have site where user need to get http basic authentication prior to access the url lets say http://ift.tt/2bLcBFa. Basic authentication can be passed in either way

1. Browse the url and enter the username, password on the pop-up if not done already.

2. Access the url as: username:password@http://ift.tt/2bLcBFa

Now I use approach #2 supply the basic auth credential via url itself. This works fine and I can able to see the legitimate web page but When I open firebug and see the all loaded static files it shows me something like

http://ift.tt/2bSaKfz
http://ift.tt/2bLcB8g
http://ift.tt/2bSbaSX

Please note the prepend text username:password@ in the url. I don't want that I just want these static files to be loaded normally like

http://ift.tt/2bLcV76

I don't know if this is something done by the browser or apache server. Would be appreciated even if share some useful link that I missed to google.