diff --git a/wp-includes/js/thickbox/thickbox.js b/wp-includes/js/thickbox/thickbox.js
index 5bca4b1295..09c8a993a1 100644
--- a/wp-includes/js/thickbox/thickbox.js
+++ b/wp-includes/js/thickbox/thickbox.js
@@ -130,7 +130,7 @@ function tb_show(caption, url, imageGroup) {//function called when the user clic
 
 			TB_WIDTH = imageWidth + 30;
 			TB_HEIGHT = imageHeight + 60;
-			jQuery("#TB_window").append("<a href='' id='TB_ImageOff' title='"+thickboxL10n.close+"'><img id='TB_Image' src='"+url+"' width='"+imageWidth+"' height='"+imageHeight+"' alt='"+caption+"'/></a>" + "<div id='TB_caption'>"+caption+"<div id='TB_secondLine'>" + TB_imageCount + TB_PrevHTML + TB_NextHTML + "</div></div><div id='TB_closeWindow'><a href='#' id='TB_closeWindowButton' title='"+thickboxL10n.close+"'><div class='tb-close-icon'></div></a></div>");
+			jQuery("#TB_window").append("<a href='' id='TB_ImageOff'><span class='screen-reader-text'>"+thickboxL10n.close+"</span><img id='TB_Image' src='"+url+"' width='"+imageWidth+"' height='"+imageHeight+"' alt='"+caption+"'/></a>" + "<div id='TB_caption'>"+caption+"<div id='TB_secondLine'>" + TB_imageCount + TB_PrevHTML + TB_NextHTML + "</div></div><div id='TB_closeWindow'><a href='#' id='TB_closeWindowButton'><span class='screen-reader-text'>"+thickboxL10n.close+"</span><div class='tb-close-icon'></div></a></div>");
 
 			jQuery("#TB_closeWindowButton").click(tb_remove);
 
@@ -195,7 +195,7 @@ function tb_show(caption, url, imageGroup) {//function called when the user clic
 					urlNoQuery = url.split('TB_');
 					jQuery("#TB_iframeContent").remove();
 					if(params['modal'] != "true"){//iframe no modal
-						jQuery("#TB_window").append("<div id='TB_title'><div id='TB_ajaxWindowTitle'>"+caption+"</div><div id='TB_closeAjaxWindow'><a href='#' id='TB_closeWindowButton' title='"+thickboxL10n.close+"'><div class='tb-close-icon'></div></a></div></div><iframe frameborder='0' hspace='0' src='"+urlNoQuery[0]+"' id='TB_iframeContent' name='TB_iframeContent"+Math.round(Math.random()*1000)+"' onload='tb_showIframe()' style='width:"+(ajaxContentW + 29)+"px;height:"+(ajaxContentH + 17)+"px;' >"+thickboxL10n.noiframes+"</iframe>");
+						jQuery("#TB_window").append("<div id='TB_title'><div id='TB_ajaxWindowTitle'>"+caption+"</div><div id='TB_closeAjaxWindow'><a href='#' id='TB_closeWindowButton'><span class='screen-reader-text'>"+thickboxL10n.close+"</span><div class='tb-close-icon'></div></a></div></div><iframe frameborder='0' hspace='0' src='"+urlNoQuery[0]+"' id='TB_iframeContent' name='TB_iframeContent"+Math.round(Math.random()*1000)+"' onload='tb_showIframe()' style='width:"+(ajaxContentW + 29)+"px;height:"+(ajaxContentH + 17)+"px;' >"+thickboxL10n.noiframes+"</iframe>");
 					}else{//iframe modal
 					jQuery("#TB_overlay").unbind();
 						jQuery("#TB_window").append("<iframe frameborder='0' hspace='0' src='"+urlNoQuery[0]+"' id='TB_iframeContent' name='TB_iframeContent"+Math.round(Math.random()*1000)+"' onload='tb_showIframe()' style='width:"+(ajaxContentW + 29)+"px;height:"+(ajaxContentH + 17)+"px;'>"+thickboxL10n.noiframes+"</iframe>");