ASHLAND, Ky. - What happened and why?

Those are the questions remaining after a chemical incident early Saturday morning that sent three people to King's Daughters Medical Center in Ashland, Ky., and shut down part of the emergency room there for a time.

Area emergency services personnel responded to the hospital with full hazardous materials gear after being alerted that a patient had possibly come into contact with an unknown substance.

"We were told a woman had come into the hospital complaining of feeling ill and she said she thought water in the Ohio River was what made her sick," Ashland-Boyd County- Catlettsburg Emergency Management Agency Director Matthew Adkins said. "She had brought a sample of river water with her."

The water sample was collected and tested using a HazMat kit, a field testing unit that can determine the chemical composition of possible contaminants.

The river water sample the woman brought to the hospital was found to contain a hydrocarbon in the fuel oil family, possibly diesel fuel, Adkins said.

It is not known at this time how the fuel oil got into the river or even how much is in the river.

"We do know the sample had low levels of diesel fuel in it, but this is not necessarily indicative of how much fuel might be in the river," said Ashland Fire Department Senior Capt. Jon Pennington.

The woman and two people who came to the hospital with her are believed to be employees on a barge that was docked on the river near South Point.

She was treated for her symptoms and the other two people were kept at the hospital for a time for observation. The incident shut down part of the hospital's emergency room for a time, Adkins said.

The incident drew attention from Lawrence County emergency services and government officials. Ironton Fire Chief Tom Runyon watched with others as the water sample was tested.

He said there were concerns on this side of the river about the effect a chemical might have on the city's water supply - at a time when the city's water supply has been fraught with water line breaks.