Twitter's IT security head Bob Lord reported the attack in a blog. To ensures security, the company said it had reset passwords for the affected accounts and was getting in touch with the account owners via email.
The company called the culprits "extremely sophisticated" and said it believed other companies and organisations had also been recently "similarly" attacked.
Twitter did not however draw a direct connection to developments earlier this week, when three of the country's top newspapers reported they suspected Chinese hackers were behind ongoing cyber attacks.
The Washington Post was the latest to report the attacks, saying Saturday that it suspected Chinese hackers were behind a"sophisticated cyber attack" on its systems.
The Wall Street Journal Thursday reported that it was attacked by Chinese hackers, a day after The New York Times said similar attacks had been going on for four months.
The Post said the attack was discovered in 2011 and reported by an independent cyber security blog on Friday.//DPA