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Dennis Patrick O'Berg


On September 11, 2001, terrorists attacked the World Trade Center in New York City.The first attack came at 8:48 a.m. when a hijacked airliner crashed into the North Tower. Numerous FDNY units witnessed the attack and a third alarm assignment was immediately dispatched. Upon their arrival at the incident scene, the focus of the firefighters’ efforts was the rescue of civilians trapped in the burning tower. At 9:02 a.m., a second hijacked airliner struck the South Tower. Firefighters immediately began to climb to the upper floors of the second tower to evacuate trapped civilians. At 9:50 a.m., the South Tower collapsed, killing scores of firefighters. The North Tower collapsed at 10:28 a.m., killing many more.341 FDNY firefighters were killed, from the Chief of Department to probationary firefighters with less than a month on the job.
photo of the National Fallen Firefighters Memorial
Dennis Patrick O'Berg was honored on the National Fallen Firefighters Memorial in Emmitsburg, Maryland and was included in the USFA’s annual report Firefighter Fatalities in the United States.

Department information

Fire Department City of New York
9 MetroTech Center
Brooklyn, New York 11201

Chief: Fire Commissioner Thomas Von Essen

Rank: Firefighter
Classification: Career
Incident date: September 11, 2001 09:50
Date of death: September 11, 2001
Cause of death: Collapse
Nature of death: Trauma
Activity type: Search and Rescue
Emergency duty: Yes
Duty type: On-Scene Fire
Fixed property use: Store/Office

Last updated: April 17, 2017