Brasilia: Hackers penetrated Brazil`s foreign ministry internal email system but failed to get access to confidential government documents and cables, a ministry spokesman said on Tuesday.
No group immediately claimed responsibility for the attack on Monday, which came amid protests by groups opposed to Brazil hosting the World Cup in June and July.
Police and government security teams were investigating the extent of the attack. The ministry shut down its email communications for a day.
The spokesman said sensitive information sent through the email system was encrypted, but employees at the ministry and Brazilian embassies abroad were told to change their passwords.