UPDATE 1305 GMT: Now to the Important Question....Which Iranian official started the story of the captured troops and why?
Starting point has to be the Revolutionary Guard, given that its outlet Javan (again, not Fars, which may have repeated the story but soon deleted it) started the rumour. But with Javan soon pulling its attempted scoop and apologising, I doubt anyone will be admitting responsibility.
Indeed, Press TV brings a smile with its coverage: "Iran's Islamic Revolution Guards Corps (IRGC) rejects rumors of seven US troops being detained on the border of southeastern province of Sistan-Baluchestan."
Somehow, Press TV forgets to mention who started those rumours....
UPDATE 1225 GMT: Mystery Solved. Javan, which started the story that seven US troops had been captured, has just posted that "the news is not true" and has apologised to its readers.