United Airlines Bloodied Passenger Bolted Back Onto Plane

The United Airlines passenger who was grabbed and dragged off a flight Sunday ... somehow got back onto the jet -- and seemed extremely disoriented and confused.

The man, reportedly a doctor, ran down the aisle, yelling ... "I have to go home! I have to go home!" He also mumbled, "Just kill me. Just kill me." You could see he was bloodied from the first time he was removed.

He was eventually escorted off the plane ... again.

United says this was all due to overbooking, and the CEO apologized for "re-accommodating" the passengers.

11:32 AM PT -- Chicago PD says the man who got dragged off the United Airlines flight had been asked to leave before authorities arrived. Cops say he began yelling at the request, at which point Aviation Officers tried forcibly removing him. He fell during the struggle and struck an armrest, causing injuries to his face. They add ... he was taken to a nearby hospital with non-life threatening injuries and an investigation is ongoing. Also ... he's 69 years old.