CHARLESTON (REUTERS) - A chemical spill along a West Virginia river on Thursday has resulted in a tap water ban for as many as 300,000 people, shutting down schools, bars and restaurants and forcing residents to line up for bottled water at stores.

Governor Earl Ray Tomblin declared a state of emergency for nine counties as a result of the spill of 4-Methylcyclohexane Methanol, a chemical used in the coal industry. The spill occurred along the Elk River in Charleston, the capital and largest city of the eastern US state.

Health officials were advising residents to use the water only for flushing toilets and fighting fires.

"West Virginians in the affected service areas are urged NOT to use tap water for drinking, cooking, washing or bathing," Governor Tomblin said in a statement. "Right now, our priorities are our hospitals, nursing homes, and schools."

Local media showed pictures of West Virginia residents lining up at stores for bottled water, and store shelves that had been emptied of their supplies.

Dr Rahul Gupta, health officer for the Kanawha-Charleston and the Putnam County Health Departments, ordered closed all restaurants, body art parlours and schools that receive water from the West Virginia American Water company.

Schools would be closed on Friday across many counties, including Boone, Cabell, Clay, Jackson, Kanawha, Lincoln, Pocahontas, and Putnam, the West Virginia Department of Education said on its website.

"You can't have schools without water," said Governor Tomblin's spokeswoman, Ms Amy Shuler Goodwin. She did not know when the ban would be lifted.

Governor Tomblin said his office was working with the National Guard and the state's Office of Emergency Services to provide water and supplies through county emergency services offices as quickly as possible.

The spill originated with Freedom Industries, a Charleston company, according to Ms Laura Jordan, external affairs manager for West Virginia American Water.

It occurred right above the intake of the Kanawha Valley water treatment plant in Charleston - the largest in West Virginia - and affects 100,000 homes and businesses, or 250,000 to 300,000 people, Ms Jordan said.

"It could be potentially harmful if swallowed and could potentially cause skin and eye irritation," Ms Jordan said.

Spokeswoman Shuler Goodwin said that on Thursday morning the West Virginia Department of Environment Protection got a report of an odour - described in local media as resembling black licorice - and visited the Freedom Industries site.

There, officials found a leaking storage unit.

Ms Jordan said the water company and state environmental officials were conducting tests on the water.

The company is working with state and federal authorities to get residents access to bottled water, and water distribution sites will be announced through local media, Ms Jordan said.

A representative for Freedom Industries did not respond to requests for comment.

The company says on its website it is a producer of specialty chemicals for the mining, steel and cement industries.