Twitter has stopped working properly for some users – and it's not clear why.
People on the site report seeing issues such as an "internal server error" and problems with opening DMs or posting photos.
But the problems don't appear to be hitting every user, or every part of the service consistently.
The problems are nonetheless relatively widespread, according to the website Down Detector. They are particularly focused in Europe and Japan, the same site's outage map showed, though other regions were also affected.
The company's own status page does not show any issues, indicating "All Systems Operational".
Twitter was once known for major outages, which became so regular that its error screen and the "fail whale" that it depicted became a topic of discussion on the site. But in recent years, stability has improved and the site tends to stay online almost all of the time.
The issues came after a week of major outages that also included Nest thermostats going offline as record breaking cold arrived in the US.
Gmail was also hit by a major issue that left many people unable to read their emails.
