An envelope that arrived in the mail on Wednesday at the capital’s Evelpidon court complex prompted a security alert after it was found to contain an unidentified white powder.
The A4 envelope also contained a four-page document, according to sources who did not provide details about its contents.
Bomb disposal experts and firefighters arrived at the scene and delivered the envelope to the Center for Disease Control and Prevention (KEELPNO), which passed it on to the microbiological laboratory of Athens University for tests whose results were expected late last night.
The building in the court complex to which the letter was addressed was disinfected.
The envelope bore no details about the sender.