MovieClip: Fade Out (Previous) then Fade In (Next)

I need to produce an image gallery which when a thumbnail is pressed it loads a new image, fades out the previous image then fades in the new one.

I have it fading in but I don’t know how to fade the previous image out before.

Here is my code so far:

[COLOR=royalblue]import mx.transitions.Tween;[/COLOR]
[COLOR=royalblue]import mx.transitions.easing.*;[/COLOR]
[COLOR=royalblue]var imageLoader:MovieClipLoader = new MovieClipLoader() ;[/COLOR]
[COLOR=royalblue]var imageListener:Object = new Object () ;[/COLOR]
[COLOR=royalblue]imageLoader.addListener(imageListener); [/COLOR]

[COLOR=royalblue]imageListener.onLoadInit = function() {[/COLOR]
[COLOR=royalblue]var fadeIn:Tween = new Tween(holderMain.holderImage, “_alpha”, Regular.easeIn, 0, 100, 60, false); [/COLOR]
[COLOR=royalblue]}[/COLOR]

[COLOR=royalblue]holderMain.holderButton.button1.onRelease = function() {[/COLOR]
[COLOR=royalblue]imageLoader.loadClip(“one.jpg”,holderMain.holderImage);[/COLOR]
[COLOR=royalblue]}[/COLOR]

[COLOR=royalblue]holderMain.holderButton.button2.onRelease = function() {[/COLOR]
[COLOR=royalblue]imageLoader.loadClip(“two.swf”,holderMain.holderImage);[/COLOR]
[COLOR=royalblue]}[/COLOR]