A Missouri Amazon delivery driver who police say parked his van illegally in a handicapped-accessible parking spot is in critical condition in a hospital after a man shot him in a dispute over the space.

St Charles Police Lieutenant Tom Wilkison says the 21-year-old driver was taken on Tuesday to a hospital in critical but stable condition with a back wound.

The St Louis Post-Dispatch reports that the dispute started when a 65-year-old man pulled out a cellphone to record that the driver had parked illegally. During a struggle over the phone, the older man fell and then fired shots as the driver walked away. It wasn't known if the older man had a disability.

Amazon in a statement described the incident as "terrible". The driver works for a third-party service provider.