How to copy images to web folder with assetic

I can't believe that I'm not able to google this...

So, I have a symfony2 application, and I installed jQuery UI with Composer. That means i have project structure like this:

/app/
/src/
/vendor/components/jqueryui/
/web/

I have assetic set up to copy js/css files from the vendor folder to web. That works fine. Config:

assetic:
    assets:
        javascripts:
            inputs:
                - %kernel.root_dir%/../vendor/components/jquery/jquery.js
                - %kernel.root_dir%/../vendor/components/jqueryui/ui/jquery-ui.js
                - %kernel.root_dir%/../vendor/components/jqueryui/ui/i18n/jquery.ui.datepicker-cs.js
        stylesheets:
            inputs:
                - %kernel.root_dir%/../vendor/components/jqueryui/themes/redmond/jquery-ui.css
            filters: cssrewrite

After assetic:dump i have

/web/js
/web/css

cssrewrite rewrites images/image.png to ../images/image.png. I guess that's ok, assumes a /web/images directory with said images.

Now the question is: How do I copy the images from /vendor/components/jqueryui/themes/redmond/images to /web/images?

Or is there another best practice to do that? Excuse me if it's and obvious thing, I'm a .NET guy, just trying out PHP.