weird problem with removing files

I have a few files on my system named:

-rw-------
-rw-r-----
-rw-rw--w-
-rwxrw-r-x

(Yes, it's really the name of the file, not the access permissions, they're 0 bytes large and all created at the same date/time).

I've no idea how they got there but I don't seem to be able to delete them because rm thinks it's dealing with an option when it encounters the filename.

I tried to escape the the - like \- but it doesn't work.

It's not a big problem but I'ld like to kick those files out.

Any ideas anyone?

rm -- -rw-------

thanks,

ls | grep - | xargs rm --

got rid of all of them