How to get element name in soap message using simplexml

Hi i'm trying to get the element name from these soap message so as to determine what action to be taken however i get Body in this case accountInformationRequest is what I'm after .I am getting multiple requests on a single URL thus need to get the element name.These is what i have tried

 $xml=simplexml_load_string($content);
$xml->registerXPathNamespace('env', 'http://ift.tt/sVJIaE');
    $xml->registerXPathNamespace('ns', 'http://ift.tt/21JxpRO');
    $xml->registerXPathNamespace('ns1', 'http://ift.tt/1oUyrJ3');
    $xml->registerXPathNamespace('ns2', 'http://ift.tt/21JxpRQ');
    $xml->registerXPathNamespace('ns3', 'http://ift.tt/1oUyrZi');

 $bodies = $xml->xpath('env:Body');
 foreach($bodies as $body){

    echo $body->getName();

        $reply = $body->children('ns', TRUE)->accountInformationRequest;
}




//Soap message
        <soapenv:Envelope 
    xmlns:soapenv="http://ift.tt/sVJIaE" 
    xmlns:ns="http://ift.tt/21JxpRO" 
    xmlns:ns1="http://ift.tt/1oUyrJ3"
    xmlns:ns2="http://ift.tt/21JxpRQ"
    xmlns:ns3="http://ift.tt/1oUyrZi">
       <soapenv:Header/>
       <soapenv:Body>
          <ns:accountInformationRequest>
             <ns:security>
                <ns1:login>sam</ns1:login>
                <ns1:password>lin</ns1:password>
             </ns:security>
             <ns:hsTransactionId>001</ns:hsTransactionId>
             <ns:destinationUri>003</ns:destinationUri>
             <!--Optional:-->
             <ns:routingTag>B2B</ns:routingTag>
             <!--Optional:-->
             <ns2:vendorSpecificFields>
                <!--Zero or more repetitions:-->
                <ns3:vsf>
                   <ns3:vendorId>10</ns3:vendorId>
                   <ns3:fieldId>22</ns3:fieldId>
                   <ns3:value>2</ns3:value>
                </ns3:vsf>
             </ns2:vendorSpecificFields>
          </ns:accountInformationRequest>
       </soapenv:Body>
    </soapenv:Envelope>

via Chebli Mohamed