jQuery Grid Plugin - jqGrid

I am trying to figure out how to perform an AJAX delete. The delete button is defined in the colModel with the following options:

{name:'delete', index:'delete', formatter:'actions', width:20, editable:false, formatoptions:{editbutton:false, delbutton:true}}

I am not using any custom buttons or a pager element. How do I define the action for this button to perform a delete?