Here is unappropriate comment on others answer:
Can we remove it?
Just Flag those comments and give specific reason, which you found unappropriate. It will be removed by Moderator if your reason is valid.
METHOD 1 :
Otherwise, Do the following :
METHOD 2 :
Add your comment to the user who was posted irrelated to the content to remove the comment or ask at correct place. If they removed its fine. Or else You can go with moderator.