image in html email

I have an Edit Page, with some fields .
On this page also a field of type 'text' named "imgtext"
In this field I write html code for an image as eg. : [size="2"]<img src:"https://asprunner.com/forums/file.php?topicimage=1&fieldname=question&id=23890&image=1&table=forumtopics"/>[/size]
[size="2"]I wouldlike to send a html e-mail with the image visible in the email body.[/size]
So for now I've put this code in the 'after record updated' event.
**
$subject= [size="2"]$values["subject"];[/size]
$email=$values["email"];
$body="Here is my image \n". $values["imgtext"];
$ret =runner_mail(array('to' => $email, 'subject' => $subject, 'htmlbody' =>$body, 'charset' => 'UTF-8'));
[size="2"]if($ret["mailed"])[/size]
{ echo"email was sent";
}
if(!$ret["mailed"])
{ echo $ret["message"];
}
return true;

The email is sent but the picture does not appear in the email!.
I checked the manual on sending email but could not find a clear answer on this specific topic including images in html email.
What am Imissing ? Any help is welcome.