Advertisement PD: Man who hit 4 vehicles filmed video during hit-and-run crashes Robert Kelley IV, 18, accused of causing crashes Monday Share Shares Copy Link Copy

New Smyrna Beach police believe a YouTube video documents a teenager's wild ride down State Road 44 in New Smyrna Beach.Watch the videoThe driver is accused of causing two separate car crashes that wrecked four vehicles on Monday. Investigators believe the person behind the wheel is 18-year-old Robert Kelley IV.The car runs red lights, weaves in and out a traffic and drives on shoulders to get around other cars. Kelley allegedly hit one car before speeding off.The driver "travels about another half mile down the road and crashes into three more vehicles," said Master Sgt. Eugene Griffith. "Then tries to leave that scene also, but the vehicle was so disabled that he couldn't leave the scene of the crash."Kelley's car was mangled following the second crash, police said.Most watched video: Graduate fails at back flip on stage"He had to be extracted from his vehicle," Griffith said. "They had to cut him out of his vehicle."Kelley was airlifted to a hospital with head injuries. Three people in the other cars were taken for non-life-threatening injuries.WESH 2 went to Kelley's home and a woman there said he is out of the hospital and admitted to posting the video to YouTube. When asked why Kelley did so, though, the woman shut the door.Police said Kelley hasn't been arrested yet.Also see: Wash. family victims of 'swatting' prank"Well, the day that the crashed happened he was actually airlifted to Halifax Medical Center," Griffith said. "We became aware of this video today and we just haven't had enough time to finish up our investigation yet."Police said the investigation is ongoing.Related: Florida mug shots