NASHVILLE, Tenn. -- Police said speed and alcohol may have contributed to a fatal crash on Interstate 40 overnight.

Witnesses told police they saw the man driving at speeds of 100 mph on the interstate before he lost control. The vehicle flipped two or three times near the Wilson-Davidson County line.

An off-duty firefighter smelled gas when he stopped to help, so he reached into the car and turned the ignition off. He told police that's when several empty beer cans came out of the car.

The crash pinned the driver underneath the vehicle, and he died at the scene.

The victim’s name has not been released, but police said he is a white man in his mid-20s and lived near were the crash occurred.

Police said he was not wearing his seat belt.