Two employees of the Brazilian Foreign Ministry say the agency briefly suffered an unspecified computer outage after a flurry of suspicious emails.
The extent of Thursday's disruption wasn't immediately clear. One of the employees says ministry servers were out for several hours but that email access has been restored.
Both relayed the information on condition of anonymity as they were not authorized to speak to the media.
The ministry did not immediately return messages seeking comment.
Worries over politically motivated hacking have been accentuated by the publication of emails stolen from the U.S. Democratic Party in 2016 and members of French leader Emmanuel Macron's campaign earlier this year.
In 2014, the U.S. State Department took its unclassified email system offline in an effort to lock out persistent intruders.
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