A letter bomb was mailed to the head of Germany's biggest bank, Deutsche Bank, investigators said Thursday.
The package was intercepted before it could be delivered to chief executive Josef Ackermann, according to prosecutors in the western state of Hesse, where Deutsche Bank has its headquarters.
It was found to contain flammable powder and shrapnel that could "certainly have been dangerous" had it exploded, a police spokesman told Der Spiegel magazine.
The explosive device has since been deactivated, officials said, adding that the investigation is ongoing.
No one has claimed responsibility for the mail bomb.
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The package was flagged as suspicious as it went through a routine X-ray scan in the bank's mail room in Frankfurt, the Associated Press reported. It has been Deutsche Bank policy to scan every item of mail addressed to executives since 2006, a banking source told Reuters.
Security has been stepped up at Deutsche Bank offices around the world, Reuters reported.
Wall Street banks have been asked to put their mail rooms on alert, an unnamed executive told Bloomberg. The FBI is assessing the potential risk and does not currently believe there is any specific threat to New York, FBI spokeman James Margolin said.
Der Speigel described Swiss-born Ackermann as "one of the most controversial managers in Germany." He is one of the highest-paid executives in Germany, associated with big bonuses and shareholder-driven management.
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