Stop on-tap propagating down

Hi, I’ve got an ion-list with ion-buttons on the right of the cell, as per the documentation. Example code:

  <ion-item ng-repeat="item in items" on-tap="itemTapped()">
    <button ng-hide="hideCondition"
            class="button button-positive">
      <i class="icon ion-ios7-more"></i>

Even if I precisely hit only the button on the right, the on-tap function for the ion-item ends up firing. This is causing some odd race conditions in my code. How can I stop this happening? That is, can I activate the click event for the button only?