Police announced Tuesday that a quantity of marijuana was found in the car that was involved in a fatal head-on collision on Montauk Highway in Quogue.

Police say the driver of the Nissan Maxima, 22-year-old, Justin Mendez, was driving around a curve when he went into oncoming traffic and smashed into a car that was being used as an Uber.

The head-on collision killed Mendez, 32-year-old Uber driver Farhan Zahid, of Bay Shore, and three of his four passengers. Manhasset brothers Michael Farrell, 20, and James Farrell, 25, and their friend Ryan Kiess, 25 were all killed. Kiess' girlfriend, 22-year-old Brianna Maglio, of Garden City, survived and remains in critical condition.

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Police say in addition to the marijuana, Mendez was also spotted by witnesses and a Quogue police officer driving at a high rate of speed right before the crash. It's estimated that he may have been driving 55 mph in a 30 mph zone on a sharp curve.

Police say the officer who witnessed Mendez speeding made a U-turn and tried to follow but the crash happened seconds later.

"It's instantaneous. We have evidence that can demonstrate there was a brief view of the vehicle, but the officer very quickly loses sight and never catches up to him," says Quogue Police Chief Christopher Isola.

Meantime, Syed Rizvi is planning a final goodbye for his brother-in-law Zahid, a married father of three.

"The reason he was working at night was to spend time with his family during the day," says Rizvi.

A funeral will be held for Zahid on Wednesday at 1 p.m. at Masjid Darul Quran in Bay Shore.

Due to the number of fatalities, the NTSB is assisting in the investigation as well as state police.

The Suffolk medical examiner would not release information on Mendez's autopsy or toxicology report.