A man accused of killing six people and injuring two more in three separate shootings Saturday evening in Kalamazoo, Mich., was a driver for Uber and may have picked up a fare through the ride-sharing app in between shootings, according to media reports.

Jason Brian Dalton, 45, of Kalamazoo, first allegedly shot a woman multiple times in the parking lot of the Meadows Townhomes, according to the Michigan State Police. He then allegedly shot and killed two people, a father and son, at the Seelye Ford KIA Dealership. In the third attack, Dalton is accused of shooting five people outside a Cracker Barrel Restaurant, four of whom died as a result of their injuries.

Sources told CNN that Dalton picked up and dropped off Uber passengers between the shootings.

“We are horrified and heartbroken at the senseless violence in Kalamazoo, Michigan,” Uber Chief Security Officer Joe Sullivan said in a statement. “Our hearts and prayers are with the families of the victims of this devastating crime and those recovering from injuries. We have reached out to the police to help with their investigation in any way that we can.”

“There's a full background check done on all driver partners for Uber and this individual had the background check completed and there was nothing in his background to indicate he was a problem,” Ed Davis, a member of Uber's safety advisory board, told ABC’s Good Morning America. “He had no record whatsoever.”