A letter bomb addressed to Deutsche bank CEO Dr. Josef Ackermann was found in the mailroom of the bank's Frankfurt headquarters this morning. The bomb did not detonate, and no one has claimed responsibility yet. (ABC reports that Ackerman "is one of Europe's most powerful bankers and is a key advisor in the European Union debt crisis to Germany's Chancellor Angela Merkel.") We hope you didn't have any big heist plans cooking this week, because now the NYPD is warning local banks to step up security.

Some 10,000 security officials who participate in the NYPD SHIELD counterterrorism program have been alerted this afternoon. (SHIELD encourages private sector security officials to undergo counterterrorism training and liaison with the NYPD.) The warning to bank security officials reads in part: "We have received a report of a confirmed mail (package) explosive device that was addressed and sent to ... Deutsche Bank in Frankfurt, Germany. The package was detected by X-ray technology inside the mail room. The package did not detonate."

Reuters reports the package carried a return address from the European Central Bank’s [ECB] Frankfurt headquarters. Forbes says the news comes "with a big weekend looming in Europe. The ECB is meeting on interest rate policy Thursday." (That is, if they can lay off the letter bomb pranks for a day.)