Authorities are investigating the circumstances surrounding the death of a man who died Wednesday night after D.C. emergency responders went to the wrong address, D.C. Fire Chief Dennis Rubin said.

The delays caused the ambulance to take more than 34 minutes from the moment the 911 call went out until the time the patient was transported to Howard University Hospital. Rubin called the delay an “operational error” and has ordered a review of the incident.