SAN MATEO, Calif. (KGO) -- A driver recorded video of a man apparently sleeping at the wheel of his Tesla.The Tesla was spotted heading northbound on Interstate 280 in San Mateo, and appeared to be in autopilot mode. In the video, the Tesla driver's head is tilted back."I followed him for a few miles and noticed the majority of the time his head was back and sometimes he popped his head forward," said the person who recorded of the video. "I was able to catch up to him and recorded as much as I could, but eventually slowed down because I could not keep up with his constant high speed."The CHP says it got a call about a sleeping driver Monday afternoon but they were unable to locate him.Tesla has warned drivers they must be alert with their hands on the wheel, even when the vehicle is on autopilot.