Investigators now say speed may have been a factor.
As CBS2's Jennifer McLogan reported, somber Quogue Village officials were joined by State Police to announce, due to the tragic number of deaths in Saturday's Montauk Highway Crash, the NTSB and attorney general are now assisting in the investigation.
Officials say 22-year-old Justin Mendez, alone in his vehicle, may have been speeding, and possibly turned off his headlights to avoid detection.
"There was a radar clock on there... He spots Mendez about 1,000 feet into the Village of Quogue, goes through a sharp turn heading west, that is where the officer observes him," said Quogue Village Police Chief Christopher Isola.
The officer made a U-turn to pull over the car, activated his strobe lights, but doesn't know if Mendez saw him.
"There was a very brief view of the vehicle, but the officer very quuicky loses sight and never catches up to him," Isola said.
Justin's parents say he was studying media in college, had a full time job, was respectful and honorable, and call speeding out of character.
"I can't express the heartache and the pain for the other families that are involved in this situation," Justin's father Octavio Perez said.
Just prior to the fatal collision, four friends called an Uber to a nearby summer cottage in Remsenberg to take them dancing in Southampton. The Farrell brothers, Andrew and Michael - three sport stars - and best friend Ryan Keiss, all of Manhasset. Ryan's Garden City girlfriend Brianna Maglio, who remains in critical condition, has been transferred to Northwell's South Shore University Hospital.
Meanwhile, Uber driver Farhan Zahid's widow is trying to explain to their three children that their father is not coming.
"Crying. It's a big loss," said Hifsa Ahmed.
Local residents say they call the curve worrisome and treacherous.
"I don't know how much worse it needs to be to prove to Suffolk County that we need to redesign this particular stretch of Old Montauk Highway to be safe," Quogue resident Melissa Barret said.
Blinking lights are now joined by a speed monitor at the site.
There is no criminal investigation because Justin Mendez died in the crash. It's unclear if the medical examiner will issue autopsy results.
"There was a quantity of marijuna found in the vehicle, within the passenger compartment," Isola said.
Meanwhile, a prayer service for the victims of the crash will be held Tuesday night at the Church of Saint Mary in Manhasset.
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