Dynamic checkbox component in Lightning, unable to get event in controller

I am creating dynamic checkbox component in Lightning in helper class but I am not able to capture click event in controller class as value is undefined for event.

Helper

 var checkBoxDef = [];
 var checkBoxCmps = [];

 checkBoxDef.push([

                "ui:inputCheckbox",

                    {
                       "class" : "design-checkbox",
                        "id" : "accordion-c-"+i,
                        "aura:id" : "accordion-c-"+i, 
                         "click": component.getReference("c.handlePress")
                    }

            ]);

 $A.createComponents(
        checkBoxDef,
        function(cmps, status, errorMessage){
            if (status === "SUCCESS") {
                for (var i = 0; i < cmps.length; i++) {
                    var checkBoxCmp = cmps[i];              
                    checkBoxCmps.push(checkBoxCmp);
                }
            }
            else if (status === "INCOMPLETE") {
                console.log("No response from server or client is offline.")
            }
            else if (status === "ERROR") {
                console.log("Error: " + errorMessage);
                }
            }
        ); 

Controller

handlePress : function(component) {
        var sectionId;
         console.log(component);

       if (event.target != undefined) {
           sectionId = event.target.id;
        } else {
            sectionId = event.getSource().getLocalId();
             }
         }   

Error

This page has an error. You might just need to refresh it. Action failed: c:CCustomLightningPage$controller$handlePress [Cannot read property 'target' of undefined] Failing descriptor: {c:CCustomLightningPage$controller$handlePress}