The BBC is the latest high-profile organisation to have its Twitter feed breached.
Several BBC Twitter accounts, including its weather, Arabic and Radio Ulster feeds were hijacked by a group calling itself Syrian Electronic Army.
The group has previously spread messages in support of Syrian president Bashar-al-Assad, the BBC said.
According to the BBC, it has regained control of all accounts and has deleted all “inappropriate content” posted by the hackers.
A BBC spokeswoman said: "We apologise to our audiences that this unacceptable material appeared under the BBC's name."
The BBC was alerted to the attacks on 21 March. At the same time, staff were alerted to a phishing email sent to some BBC email accounts, but it is not clear if the two are related, the BBC said.
Before the BBC regained control of the weather feed, the hackers were able to post messages alongside standard content.
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The tweets included: "Saudi weather station down due to head-on collision with camel,” and “Chaotic weather forecast for Lebanon as the government decides to distance itself from the Milky Way."
On the BBC’s Arabic Twitter feed, several pro-Assad messages were posted.
The hijacking of the BBC Twitter feeds come a month after similar actions involving the Twitter feeds of Burger King and Chrysler.
Two weeks earlier, Twitter was forced to reset 250,000 account passwords after a hacker attack on its systems.
News of the BBC Twitter feed hijacking coincided with news that Apple is to introduce 2FA for iCloud and other services to help protect users from hackers trying to access their accounts.