Two nights since a chemical spill in a West Virginia river left residents and businesses in nine counties unable to use their tap water for anything other than flushing the toilet, hundreds of thousands remain affected and several have been hospitalized after complaining of symptoms like nausea and vomiting.

Saturday began the third day since about 300,000 people were told not to use their tap water for drinking, bathing, cooking or washing clothes or dishes after a chemical foaming agent seeped into the Elk River from a storage tank owned by Freedom Industries.

More than two dozen people have sought medical treatment for nausea and vomiting, and four of them were hospitalized, according to The Associated Press.

Freedom Industries, a purveyor of specialty chemicals for the mining, steel and cement industries, said an unknown amount of the chemical 4-methylcyclohexanemethanol, or crude MCHM, which is used in processing coal, was found leaking from the bottom of a storage tank at its facility in Charleston.

Officials are still trying to determine how much of the chemical leaked into the river and the extent to which the regional water supply has been contaminated.

The tank reportedly holds at least 40,000 gallons, and officials believe no more than 5,000 gallons leaked from the tank, and that some of the leakage was contained before seeping into the river, according to the AP.

West Virginia Gov. Earl Ray Tomblin declared an indefinite state of emergency in nine counties Thursday night following reports that the chemical spill had led to the contamination of local water supplies.

"We encourage all individuals to determine whether their home or business is in the affected service areas," Gov. Tomblin said in a statement Friday afternoon. "One indicator of the contaminated water is the odor of the water. We urge all residents in the affected areas to follow West Virginia American Water Company's 'do not use' order until it is lifted. This includes water companies supplied by West Virginia American Water in this area. If you live in one of these areas, do not use tap water for drinking, cooking, cleaning, washing, or bathing. At this time, I do not know how long this will last."

Although the water supply is considered contaminated, access to water has not been shut off for any residents, the governor's office said.

Jeff McIntyre, president of West Virginia American Water, told the AP that the utility is working with a Tennessee-based company that makes crude MCHM to find out how much of it can be in the water without posing harm to residents.

"We don't know that the water's not safe. But I can't say that it is safe," McIntyre said Friday.

Freedom Industries president Gary Southern apologized for the incident.

"We'd like to start by sincerely apologizing to the people in the affected counties of West Virginia," Southern said. "Our friends and our neighbors, this incident is extremely unfortunate, unanticipated and we are very, very sorry for the disruptions to everybody's daily life this incident has caused."

Until the do-not-drink order is lifted, residents will have to rely on bottled water and water trucks, which Gov. Tomblin said were not in short supply.

"If you are low on bottled water, do not panic. Help is on the way. We are taking every measure to provide water to you. There is no shortage of bottled water," he said. "Supplies are moving into the area as we speak. We encourage all West Virginians in affected areas to contact their local emergency management office for water distribution sites.