Rasterize .pngs in document and move to specific layer

I am wanting a javascript that will look at the active document and find any images (.png files) and rasterize each graphic to RGB 150 ppi.

Then move the files to a layer that already exist in the document name: 1st Data

The 1st Data layer is the bottom most layer in the document if that makes a difference.

Can anyone advise as to if this is something possible to do?

Any help would be greatly appreciated!

Windows 7 64 bit and Illustrator CS4