<!doctype html>
<html>
<body onload="document.getElementById('containerA').pauseAnimations()">
  <svg id="containerA">
    <animate id="ia" end="50s"></animate>
    <animate begin="60s" end="ic.end"></animate>
  </svg>
  <svg>
    <animate id="ic" end="ia.end"></animate>
  </svg>
</body>
</html>