lucy24 - 2:37 am on May 14, 2013 (gmt 0)
"Someone or something"? Could be anything including a badly programmed robot or the googlebot's own fevered imagination. You are not obliged to adopt it, and you are not obliged to "fix" 404 errors belonging to pages that genuinely don't exist. Do you have pages containing the element "fuseaction"? If not, feed visitors a 410 and think no more about it.
RewriteRule fuseaction - [G]
A 410 is not 100% honest if the page never existed, but it will make the googlebot go away sooner. (Doesn't appear to work on bingbot-- but I don't think a 410 makes it more persistent than a 404.)