PHILADELPHIA (CBS) — The Department of Homeland Security and Philadelphia police are investigating after a suspicious package scare outside a historic site in Old City.

Officials say it was left to stoke fears of retaliation by extremists in the wake of the killing of Osama bin Laden.

 It happened around 1:45 p.m. outside the First Bank of the United States building on Third Street between Chestnut and Walnut.

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Philadelphia police chief inspector Joe Sullivan says a passerby alerted National Park Service ranger to a suspicious-looking pipe on a bench outside the building:

“It was a metal, cylindrical device capped at the top, wrapped in electrical tape.”

He says the bomb squad detonated it:

“They made a visual inspection and determined that it contained no hazardous materials or explosive materials, and right now it’s a criminal investigation.”

A number of federal and local agencies are in on a hunt for a suspect, including Homeland Security, the ATF, and Philadelphia police.

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Several streets in the area were closed for several hours and buildings in the area were evacuated, but officials say no one was hurt.

Philadelphia’s historic areas are among those under a heightened sense of awareness after the killing of Osama bin Laden. Sullivan says he believes someone wanted to take advantage of people’s fears:

“It was definitely an intentional act. It was meant to cause panic and alarm.”

The Bank building is not currently open to tourists. Sullivan says the National Park Service, which manages the Bank building, is looking into whether security cameras could have captured an image of the suspect.

Reported by Ian Bush, KYW Newsradio

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