Twitter log-ins are currently not working for a multitude of users in Pakistan, the ProPakistani team has confirmed through multiple sources.
The website itself is working perfectly fine. It still lets you browse and interact with everything, but those who are logged in are unable to log out or switch accounts, while those who are not logged in are unable to get in.
However, the issue appears to be limited to the web version of Twitter as the Android app is allowing log-ins at the time of writing.
It is unclear if this is a widespread disruption or if the issue is limited to Pakistan and some other regions. There are currently not many reports on DownDetector, the website that tracks app outages.
Let us know in the comments if you are able to log in/log out of your account or switch to a different profile.