javascript: Get src and set as variable via class (id not available)

I'm trying to get the URL of a certain image out of the given HTML code


<div class="image_div_name">
    <img src="http://ift.tt/1Ei881f" alt="">
</div>

So this is my currect code that should solve it:


var picture = document.getElementsByClassName("image_div_name");
var src = picture[0];

If I now print picture via console.log, I get the correct div:


<div class="image_div_name">
    <img src="http://ift.tt/1Ei881f" alt="">
</div>

However, if I want to access the src, it doesnt seem to work:


 var src = picture[0].src;
 console.log(src);

Gives back:


undedfined

If I try:


console.log(picture[0].innerHTML)

it gets better and I receive:


 <img src="http://ift.tt/1Ei881f" alt="">

However I'm looking for way to merely get the URL itself, as in:


http://ift.tt/1Ei881f

Can you help? What am I doing wrong?

javascript