CENTER CITY (WPVI) -- Police say a driver may have lost consciousness from misusing medical marijuana before his vehicle hit several pedestrians and another vehicle outside a hospital in Center City Philadelphia on Friday afternoon.
The crash happened at 10th and Sansom streets just outside the emergency room at Thomas Jefferson University Hospital around 4 p.m.
According to investigators, a 68-year-old man behind the wheel of Dodge Challenger lost control while driving southbound on 10th when he jumped the curb and struck three people who were walking on the sidewalk.
The impact left three people ages 64, 51 and 39 in critical condition.
Police said the Challenger then crossed Sansom and hit a Nissan Rogue SUV with a family of three inside.
Those family members - a 31-year-old man, a 56-year-old man and a 75-year-old woman - are in fair condition.
Alex Jackson of Logan said his brother, nephew and mother were in the SUV that was hit. His mother had just been discharged from the hospital moments earlier.
"She's fine now. She's just a little shook up but they are going to let her go back home," said Jackson.
The driver of the Challenger is also in stable condition.
Philadelphia Police Chief Inspector Scott Small said a preliminary investigation reveals the driver may have been unconscious or semiconscious as a result of medical marijuana.
Small said investigators are working to obtain a search warrant to draw blood from the driver.
If he is found to be over the legal limit of medical marijuana or under the influence of another substance, he will be charged with aggravated assault by vehicle.
Jackson said he's grateful for the hospital staff who sprang into action.
"I thank them very much for all the staff and everybody that helped out," said Jackson.
Earlier reports from the scene about a child being injured in this incident are unfounded, police say.
Philadelphia police: Driver hit pedestrians, SUV outside Thomas Jefferson University Hospital