From around 8:10 a.m. EST, Twitter users around the world have been reporting interrupted connections or downtime. Widespread outages are preventing users from logging in or accessing parts of Twitter's services. It's unclear which regions users are most affected by, but the service is apparently down.
According to Down Detector, reports of outages began around 8:10 a.m. ET. The reason for the outage is unclear, and Twitter has not released any official statement acknowledging the problem.
The Down Detector map shows reported outages in the US and other countries. The Twitter service itself appears to be affected, rather than an isolated server, data center, or specific function failure.