The New York Police Department said Petraeus' secretary opened a package around noon Tuesday at his office in the Solow Building and discovered what she believed to be a real grenade, NY1 news reported Wednesday.
Police evacuated the office and shut down the street outside. The object was brought to the building's courtyard, where it was found to be a "novelty item" sent to the general by a friend, police said.
It was unclear Wednesday whether Petraeus was inside the building at the time of the incident.
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