Trying to add image for menu items

Trying to add image for menu items

This is menu items and giving the image class in City menu item for example
<p:submenu label="Address">
<p:menuitem value="Country" url="/secured/country.xhtml?redirect=true" />
<p:menuitem value="State" url="/secured/state.xhtml?redirect=true" />
<p:menuitem value="City" url="/secured/city.xhtml?redirect=true"
icon="images"/>
<p:menuitem value="Location" url="/secured/location.xhtml?redirect=true" />
</p:submenu>
And this is my CSS class
.images{
background: url('../resources/images/admini.ico') no-repeat;
height:16px;
width:16px;
}
a upword arrow mark appears instead of an image
help me out with this problem