Twitter is down for many users in the UK, with the social media platform's website and mobile apps inaccessible.
The micro-blogging site has tweeted from its official support account to acknowledge the problem, which an error message on the Twitter homepage calls a "technical problem".
It read: "Some users are currently experiencing problems accessing Twitter. We are aware of the issue and are working towards a resolution."
According to the website Down Detector, which tracks outages on major websites, the issue began at around 8.30am, with the number of reported problems from users rising rapidly.
More than half of those who reported an issue did so concerning the website, but users of the iOS and Android mobile apps also reported problems.
At 9.50am the site available again from Press Gazette's computers in London.