Atlanta Police were trying to figure out Saturday what led to an accident that left a motorcyclist lying in the emergency lane with his bike.

The unidentified motorcyclist was found unresponsive with a head injury and taken to Grady Memorial Hospital, police spokeswoman Kim Jones said.

Police found the man after being called to I-20 westbound, just east of Lee Street, around 7:30 a.m. They didn’t know whether he had been struck by another vehicle or if the cyclist struck the median wall after losing control.

Police said there were no witnesses on the scene when they arrived and they encouraged anyone with information about the accident to call 404-765-2808.