a loader of *bullcrap*

import flash.display.Loader;

var loader:Loader = new Loader();
loader.load(new URLRequest(url));
loader.contentLoaderInfo.addEventListener(Event.COMPLETE,
    function(e:Event):void {
        while(background.numChildren > 0){
            background.removeChildAt(0);
        }
        //will add the Loader to the display list, should be sufficient unless you need image manipulation
        background.addChild(loader);
    });