Ion-scroll is not working with zoom In

ionic-v1
1

I think ion-scroll let img freezing(the size of the image is bigger than ion-content).
the image under ion-content doesn’t move.

<ion-view view-title={{title}}>
  <ion-content>
    <ion-scroll direction="xy" scrollbar-x="false" scrollbar-y="false" zooming="true" min-zoom="{{zoomMin}}" delegate-handle="image" style="width: 100%; height: 100%">
      <div class="item item-image" style="width:100%; height:100%;">
        <img ng-src={{src}} />
      </div>
    </ion-scroll>
  </ion-content>
</ion-view>

but without ion-scroll, the img scrolled perfectly.
any ideas?