Twitter says 130 accounts were targeted in a major cyber-attack of celebrity accounts two days ago.
However, Twitter says only a "small subset" of those 130 accounts had control seized by the attacker.
The security breach saw accounts including those of Barack Obama, Elon Musk, Kanye West and Bill Gates tweet a Bitcoin scam to millions of followers.
Twitter said it was still trying to work out if private data - which could include direct messages - was stolen.
"We're working with impacted account-owners and will continue to do so over the next several days," the company said, through its official support account.
"We are continuing to assess whether non-public data related to these accounts was compromised," it added.
Twitter says it is still looking into "what other malicious activity they may have conducted or information they may have accessed".
The private messages of Kayne West, Kim Kardashian West and Elon Musk could be worth money on dark web forums. Selling the private messages of presidential hopeful Joe Biden or former mayor of New York Michael Bloomberg could also have political consequences.
However, the BBC has spoken to one hacker who specialises in social media account takeovers and has been part of a hacking group with one account suspected of involvement.
"Honestly, I think the hack is over because I feel this may have been a quick money grab and run situation," he said.
"If they do have the DMs, they will be extremely careful with who they sell them to, if they do, because it increases their chances of being caught by quite a bit."
