A plane flying to Barcelona was grounded after a "biohazard" was declared when a passenger suffered a bout of diarrhoea.
The flight - with more than 336 people on board - was forced to turn around after a traveller "had diarrhoea all the way through the plane".
The Delta aircraft had already left Georgia and was above Virginia when the pilots decided to make an emergency landing.
In a video shared online, the pilot told air traffic control: "This is a biohazard issue.
The Delta aircraft had already left Georgia and was above Virginia when the pilots decided to make an emergency landing
Reuters
"We have had a passenger who has had diarrhoea all the way through the airplane, so they want us to come back to Atlanta."
Witnesses who claimed to be on the doomed DL194 flight shared what they had seen.
One person said: "I was on this flight! The culprit diarrheaed as he walked up the aisle from the back rows toward the bathroom.
"Then as the plane ascended he slid on the poop like ice skates all the way to the back rows again, leaving actual poop skid marks in the aisle. Total Tom & Jerry stuff."
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Another passenger onboard also praised the cleanup operation.
John Hurdt said: "Both my wife and I were on the flight. It was a mess. The pilots made the right decision to turn around.
"The ground crew ripped out the carpet and put new in.
"Considering the circumstances, the ground crew did a great job, along with the attendants and the pilots."
A woman added: "My partner was on that flight! It was pretty bad. It was dribbling down the aisle, smelled horrible.
"The vanilla scented disinfectant used on it only made it smell like vanilla s***.
One passenger onboard praised the cleanup operation following the incident
Reuters
"After the plane landed, it was thoroughly cleaned. They did not leave until around 2.30am.
"The flight was met by emergency vehicles and EMTs carried the sick passenger off the plane.
"My partner said the plane was cleaner when they got back on at 2am than it was the first time they got on. No smell either."
A Delta spokesperson said: "Delta flight 194 from Atlanta to Barcelona returned to Atlanta following an onboard medical issue.
"Our teams worked as quickly and safely as possible to get our customers to their final destination.
"We sincerely apologize to our customers for the delay and inconvenience to their travel plans."
