ST. PAUL, Minn. (WCCO) – St. Paul Police are asking the public’s help in finding the driver responsible for a hit-and-run that sent a 13-year-old boy to the hospital Monday afternoon.

Brandon Smith was left unconscious in the middle of the street near  University Avenue and Grotto Street. Police believe several cars passed him while he was lying in subzero temperatures for more than 10 minutes.

Sgt. Paul Paulos said officers found Smith  unconscious and unresponsive.

At the moment, police have little evidence to work with when it comes to finding the car involved.

“We did find evidence at the scene of a mirror, a side mirror, to a vehicle with black vehicle parts,” Paulos said.

But that’s not much to go on.

“We have no way of identifying the car at this time,” Paulos said.

Smith was on his cell phone, talking to his mother, minutes before he was hit, police say.

Crews brought Smith, who suffered head injuries, to Regions Hospital, where doctors are keeping an eye on him.

Police say a bus stop and light rail make the Grotto-University intersection a busy one. That’s why investigators believe someone might have seen something that can help bring the person responsible to justice.

Investigators are checking Metro Transit as well as CCTV to see if the hit-and-run was caught on video.

If you know anything, call St. Paul Police at 651-266-5729.