Twitter on Friday said a system change that was initiated earlier than planned affected its services, leading to a global outage.
Several users reported having issues with the micro-blogging platform early on Friday morning.
There was an irregularity with Twitter application programming interfaces (APIs) as some parts of the service were able to load but users reported that tweets were not flowing into timelines.
"We're working hard to bring Twitter back to normal and expect things to be fully resolved in 1-2 hours. We appreciate your patience," Twitter Safety said in a tweet.
In an earlier tweet, the company said Twitter has been down for many and it was working to get it back up and running.
"We had some trouble with our internal systems and don't have any evidence of a security breach or hack," it said.
Later, it acknowledged that a system change caused the outage worldwide.
"Most of you should be back to Tweeting. Twitter should be working as expected for everyone," the company informed.
On October 1, Twitter users from different parts of the world, including in India, reported problems using the platform.
Most of the problems were reported by desktop users, followed by Android and iOS users, according to Downdetector which offers real-time status and outage information.