About 40% of New York 9/11 victims' remains have yet to be identified

• The two new identifications, the 1,648th and 1,649th victims, came after decades of negative results from the office's DNA laboratory, it said.
• The victims, whose names were withheld from the public at the request of their families, were the first to be identified since September 2021. A total of 59.9% of victims have now been identified.
• The office said it also determined that 60 other human remains were from previously identified victims.

The big picture: Determining who the 9/11 victims were remains the largest and most-challenging forensic identification effort ever, according to the National Institute of Standards and Technologies (NIST).

• It has involved testing thousands of DNA samples derived from human remains collected at the site to samples collected from personal items of missing people, their relatives or other collected remains.

• In many cases, however, the victim's DNA was severely degraded by exposure to the intense heat of the burning jet fuel and months of moisture after the attacks.
• The investigation has actually lead to the development of new DNA sequencing techniques and has been help by new technologies, according to NIST.

Go deeper: Post-9/11 first responder deaths now nearly equal to attack casualties