HOUSTON -- Police said man who was speeding away from authorities struck a concrete wall and leapt 50 feet to his death off a Houston highway exit ramp Sunday morning.

The pursuit began after a deputy with the Harris County Constables stopped the man for a traffic violation, and he became agitated and uncooperative. As the deputy talked to the man, he abruptly put his white BMW in gear and sped off, said Chief Mark Herman of the Harris County Constables.

The deputy followed him to the southbound exit ramp to Interstate 45, where he saw what appeared to be a puff of smoke as the man's vehicle struck a concrete retaining wall.

As the deputy constable pulled up to the stopped car, the driver got out of his, put one foot on the guardrail and leapt off the structure, falling down to the service road below.

He died on impact and was pronounced dead at the scene, Herman said.

Other drivers witnessed the incident Sunday morning.

The man, whom authorities are still trying to identify, was between 20 to 30 years old, Herman said. Authorities are also trying to determine if he was the owner of the BMW.

The Harris Count Constable Precinct 4 will continue to investigate the incident leading up to the man's death. The Houston Police Department will handle the death investigation.

It is not yet known whether the man was attempting to commit suicide or to flee.

The man's body has been taken to the Harris County Medical Examiner's Office for autopsy and identification.