High speeds are the suspected cause of a fatal crash in Markham Thursday morning that killed a 26-year-old man and scattered debris across a large area.

York Regional Police have closed a stretch of 16th Avenue, just west of Highway 48, as a result of the single-vehicle crash.

Police say the crash occurred sometime in the middle of the night.  A neighbour told CP24's Cam Woolley he heard a loud crash at about 3 a.m. Police are still attempting to determine the time of the crash and whether the man was the driver of the car.

Police said the man died when a car veered off the road near an S-curve, went through some trees and crashed into a commercial building on 16th Avenue, just west of Highway 48. The damage to the building was extensive.

At some point, the man was ejected from the BMW, which rolled and wound up on its roof a few metres from a veterinary clinic. Police told CP24 a passerby found the man by the entrance of the driveway shortly before 6 a.m.

He was without vital signs, on the ground near the demolished car.  Paramedics rushed the man to hospital, where he was pronounced dead. The victim's identity has not been revealed as police are still trying to locate his relatives.

Debris from the crash landed on the building's roof, and a large field of debris covered the ground around the crash site. A jacket was found in the bushes, one shoe was found on the roof and a second shoe was found in a parking lot next door. Trees on the property were also snapped.

The road will likely be closed for hours to allow police to conduct an investigation at the scene.

Motorists are being asked to avoid the area, if possible.

With files from CP24's Cam Woolley

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