According to some people on X, they shut down immediately, while rides were still active. Sounds like an unplanned (and quite crazy) action.
It was planned. What's Nigeria and Uganda gonna do?
This is hilarious. They are legally kidnappers at this point. No reason to even stop the ride and let you get out for free.
Given Uber is one of the few companies who are lucky enough to have a separate page for all the controversies on Wikipedia (https://en.wikipedia.org/wiki/Controversies_surrounding_Uber), they also have their own fair of experience with police raids on their offices. They've also used "‘kill switch’ during raids to stop police seeing data" (https://www.theguardian.com/news/2022/jul/10/uber-files-leak...) before, so I wouldn't be surprised if this was some sort of legal "kill switch" or whatever that got triggered, so they can get rid of everything faster.