An 18-year-old Forsyth County man was flown by helicopter to Grady Hospital with severe arm and other injuries Friday afternoon after being pinned under his car.

Tyler David Anderson, 18, was driving in the a subdivision on Hanna Mill Drive in the northeast corner of Forsyth County, according to police spokeswoman Karleen Chalker.

"For some reason, he lost control of his vehicle, hit a mailbox and ran through a stop sign," Chalker said.

She said he ended up traveling about a quarter of a mile before his Nissan Altima flipped and trapped him underneath.

Return for updates.