Twitter has told users they should be able to tweet again after an 'incident' forced drastic action - in the hours after numerous high profile figures' accounts were hijacked.
Users across the world had been reporting issues with the social media site - in particular tweeting - in the hours after the complex scam struck.
But Twitter has now confirmed "most accounts" are able to tweet again but that functionality "may come and go".
The likes of US presidential candidate Joe Biden, reality star Kim Kardashian and billionaire Elon Musk saw their Twitter pages used to solicit digital currency Bitcoin on Wednesday.
Those targeted appeared to be verified figures and influencers with large followings, and also included former US president Barack Obama, musician Kanye West and entrepreneur Bill Gates.
The cause of the breach was not immediately clear, but the unusual scope of the problem suggested that it was not limited to a single account or service.
More than an hour after the first wave of hacks - Twitter then took the extraordinary step of preventing at least some verified accounts from publishing messages altogether.
Verified users include celebrities and journalists, but also governments, politicians and heads of state.
And by Wednesday evening, regular unverified users were reporting issues - though it remains unclear if these problems are linked.
Downdetector.com saw a spike in reports of problems from around 10pm, from across the globe.
Forty-two percent are on the IOS app, 34 percent on the website and 22 on the Android app.
Twitter was slow in offering clarification but initially said in a statement that users "may be unable to tweet or reset your password while we review and address this incident."
"This appears to be the worst hack of a major social media platform yet," said Dmitri Alperovitch, who co-founded cybersecurity company CrowdStrike.
Publicly available blockchain records show that the apparent scammers have already received more than $100,000 worth of cryptocurrency.
Some experts said the incident has raised questions about Twitter's cybersecurity.