The robbers fired at the bus as it tried to reverse, striking Frimpong, 20, in the head. He later died in hospital and is the only reported casualty from the incident.
"The Ghana Football Association (GFA) has received with profound shock and deep sorrow the tragic news of the passing of Dominic Frimpong of Berekum Chelsea Football Club," it said.
"The incident has sent shockwaves across the entire football fraternity. The GFA extends its heartfelt condolences to the family of the deceased, his teammates, technical staff, management, and all at Berekum Chelsea during this extremely difficult time."