A plane has been diverted to Tulsa International Airport after multiple passengers complained of sickness, AP reported. Delta Airlines flight 1817 was traveling to Denver from Atlanta on Saturday when it diverted to Tulsa at about 3 p.m. after the passengers apparently became ill at the same time. Emergency Medical Services Authority spokeswoman Kelli Bruer says responders with the ambulance service have treated nine passengers suffering similar symptoms, including nausea. Bruer says one passenger was taken to the hospital as "non-emergent." She says it's unknown what caused passengers to become ill. Bruer says another passenger was taken to a hospital for unrelated medical issues. The airline says 152 passengers were on board the plane when its crew decided to divert to Tulsa after "a few" passengers reported feeling ill.