(UPDATE): The FBI on Sept. 27 released a clearer surveillance photo of two men who they said left an explosive device a few blocks from where one detonated on Sept. 17 in Manhattan's Chelsea section.
The bureau also produced a surveillance camera image of a bag from which the pair "removed an improvised explosive device."
Both men "then left the vicinity leaving the device behind but taking the luggage," the FBI said.
A resident found the device, which didn't detonate, the bureau said.
The first image -- released last Wednesday -- was taken on West 27th Street between 6th and 7th Avenues sometime between 8 and 10 p.m. Sept.. 17, "in the same hour that an explosive device had detonated on West 23rd Street."
The images released Tuesday were taken around the same time, authorities said.
Anyone who sees them, knows where to find them or has information that could help the investigation is asked to contact the FBI's Toll-Free Tipline at 1-800-CALL-FBI (1-800-225-5324).
Or go to your local FBI office, or the nearest American Embassy or Consulate.
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