Twenty-three Mississippi counties, including Claiborne, were without emergency ambulance service this morning after the only company that provided them coverage went out of business at midnight.

The state Department of Health said Emergystat shut down because of a “lack of liability insurance and serious financial problems.”

State Health Officer Dr. Ed Thompson said in a statement that his department was already receiving hundreds of phone calls Wednesday night.

“Many of the affected counties have declared pre-emptive emergency declarations allowing them to seek mutual aid from other counties or other sources,” Thompson said.

The affected counties are spread across the state. They are Amite, Coahoma, Chickasaw, Claiborne, Greene, Holmes, Jefferson, Kemper, Marshall, Neshoba, Newton, Noxubee, Panola, Pearl River, Scott, Simpson, Smith, Sunflower, Tallahatchie, Tunica, Wilkinson, Winston and Yazoo counties.

Officials said residents should continue to call 911 in an emergency.

A temporary agreement was reached overnight with American Medical Response to serve Claiborne County Hospital, Emergency Management Director Roderick Devoual said this morning.

“They arrived at 12:45 a.m. They’ll be up directly from the hospital,” Devoual said.

AMR, which provides service for Jackson and Hinds County prepared to respond in Amite, Claiborne, Pearl River and Simpson counties for 48 hours.

Plans to pursue mutual-aid agreements with services from Copiah County and with the Vicksburg Fire Department-based public ambulance service in Vicksburg will be pursued as needed, Devoual said.

City attorneys in Vicksburg could not be reached this morning.

Any stoppage in emergency service would affect emergency plans at Grand Gulf Nuclear Station in Claiborne County.

Plant officials are “working closely with county officials to ensure service is provided,” Entergy Nuclear spokesman Sharon Garrison said.

Before Wednesday’s announcement, the Vernon, Ala.-based company provided ambulance service in seven states — Alabama, Mississippi, Florida, Louisiana, Kansas, Tennessee and Virginia.

Emergystat Inc. is part of Southland Health Services, which is a wholly owned subsidiary of Tennessee-based BTHC. Among its original interests was in custom motorcycles.

In 2007, Emergystat filed for Chapter 11 bankruptcy in Tennessee. Its parent company announced it was seeking acquisition or a merger with a private company.