In Civilization 6, when you assign spies to counter-spying, you're prompted to choose which district (or city center) to assign them to. The spy then defends that district and any adjacent districts. You can have multiple spies in the same city, each assigned to a different district.
What happens if an enemy spy attempts a mission within range of multiple defending spies? Specifically:
Do multiple spies provide more defense than one spy?
Which spy gets credit/experience for catching enemy spies?