This time two unregistered accounts with successive user numbers are the ones. One posts a question while the others posts seconds later with the spam answer solicited by the off-topic question. Deleting their accounts isn't stopping the spam. I flagged but I think everyone should be on alert for this attacks.
Spammers are attacking every website. That's what spammers do; they spam.
Just flag the posts you find. If enough people flag the system will take care of things automagically. Otherwise a moderator will nuke the post when we see your flag.
We don't need a Meta post about every instance :p