Essex County Express Question (May contain spoiler)

By period3, in Arkham Horror: The Card Game

I'm playing Essex county express, and the flip side of Agenda 1a (Keep moving!) says:

"Remove the left most location from the game (...). Each investigator at that location is defeated. Each enemy and asset at that location is discarded. Discard all clues controlled by the investigators"

My question is on the last sentence. Do we discard all clues controlled by all investigators no matter where they are, or do we only discard the clues of the unlucky investigators who are at the left most location?

You discard all clues controlled by everybody, no matter where they are.