UPDATE: Twitter is now back up and running.
It's one of the most popular social media sites around, but it seems that Twitter crashed across both the UK and US this afternoon.
According to DownDetector, the issues started at around 15:07 GMT, and affected users in the UK and east-coast US.
While the reason for the outage remains unclear, of those who reported issues, 59% said they couldn't access the website, 24% were struggling with the iOS app, and 16% with the Android app.
Speaking to Mirror Online, a Twitter spokesperson said: "We experienced a brief outage across Twitter that might have affected your Timeline and ability to Tweet. It's been fixed."
The issues appeaedr to come and go, with many posting tweets about the outage while the can.

One user tweeted: "I thought I got suspended but it's just Twitter going down omg."
Another added: "I thought I didn't pay my WiFi bill. #TwitterDown."
And one joked: "How can I complain that Twitter is down if twitter is down?"
This isn't the first time that Twitter has gone down in recent months.
Back in October, Twitter experienced a similar outage, with users bet by an error message saying 'Something went wrong. Try again."
Thankfully, the outage didn't last long, and around 20 minutes after it went down, Twitter was back up and running.