Video from a gas station at the circle shows the crash and explosion, which tore off the front of the 2016 Infiniti Q50, split the rest in two and hurled Christian Gloria about 75 feet just before 4:30 a.m.
Gloria played tennis in high school and was listed on the ASA College team in Manhattan.
"Any factors such as impairment are all still under investigation," Detective Sergeant Jason Lanzilotti told Daily Voice.
DPW workers needed hours to clean up debris scattered in all directions -- including the vehicle's battery, which landed near a diner on the other side of the rotary.
The entire intersection remained closed until about 2 p.m. A quarter remained closed while Bergen County Hazmat and the state DEP conducted soil sampling and ensured no environmental hazards existed.
Lanzilotti said Gloria's speed hadn't yet been conclusively determined but that the vehicle clearly was traveling well in excess of the posted 35mph limit.
The Infinity was headed north on Knickerbocker Road when it barreled onto the island at the circle at Madison Avenue near the Dumont border and struck a huge rock in front of the monument.
The Bergen County Prosecutor's Fatal Accident Investigations Unit joined Cresskill police in probing the crash. The county sheriff's Bureau of Criminal Identification collected evidence.
The monument wasn't damaged.
Designed to look like the Washington Monument, the 66-foot tall obelisk was dedicated in 1924 in honor of 563 men and women who died in a 1918 flu epidemic while stationed at Camp Merritt, an embarkation camp that stretched over 770 acres.
Made of Stony Creek granite, it features a carved relief sculpted by Robert Ingersoll Aitken portraying a World War I doughboy with an eagle above him.
An inscription on the south side says the monument "marks the center of the camp and faces the highway over which more than a million American soldiers passed on their way to and from the World War, 1917–1919."
The dedication was made in front of nearly 20,000 people on Memorial Day 1924 by General John Joseph "Black Jack" Pershing, who led the American forces to victory in World War I.
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