You can choose to report the thread....click on the icon in the lower left of the thread that is the shape of a triangle with an ! in it. This will give you a box to type why you are reporting the thread/post to the Community Support Team and someone who has access to the forum you posted in can remove it for you.

The other way is to pm a mod/admin with your request, but that may take a bit longer for the removal to happen depending on when the mod/admin is online and gets your pm.