LA PLATA, MD. ? Tornado-ravaged cities from Missouri to Maryland picked up the pieces Monday after an unusually wide and potent swath of thunderstorms weaved their way through the eastern half of the nation, killing at least six people.

Maryland was hit especially hard Sunday evening, with a tornado causing at least three deaths and 93 injuries in two counties south of the nation’s capital. A twister caused serious damage to at least a 10-mile stretch of this town of about 6,500 _ even blowing windows out of the hospital.

“They’re banged up and shocked, and they’re frightened,” Civista Medical Center chief executive Chris Stefanides said of the injured. “I don’t think they’ve ever really seen anything like this before.”

Jack Cahalan, a spokesman with the Maryland Emergency Management Administration, said Monday that 81 people had minor to serious injuries and another 12 were critically injured.

A curfew was set in La Plata to keep people off the streets, and all public schools in Charles County were closed on Monday, officials said. About 6,500 homes in the area were without power early Monday.

Thunderstorms struck states throughout the Tennessee and Ohio valleys on Sunday. The northern edge of the system brought heavy snow to Wisconsin and Minnesota.

In Missouri, a tornado packing wind of up to 180 mph and stretching roughly two football fields wide plowed through the small town of Marble Hill, hurling a 12-year-old boy 50 yards to his death. At least 16 people were injured and several homes were destroyed.

“It took several houses completely away. Blown to sticks _ nothing left but the subfloor,” Marble Hill Police Sgt. Dennis Willis said.

The boy, Billy Hoover, was on a sleep over with friends when the tornado touched down. Two of his friends in the house walked away, as did two other occupants, but the house was left in ruins, the sheriff said.

The tornado also tossed vehicles, razed buildings and twisted tractor-trailers before it raced eastward into southern Illinois and western Kentucky.

At least 30 people were injured in Providence and Irvington, Ky., where Billy Garrett, 52, died of injuries after being thrown about 200 feet from his mobile home, said Breckinridge County Coroner Bob Rhodes.

Dozens were injured in southern Illinois and a 69-year-old woman was found dead outside her mobile home in the town of Dongola. In nearby Cypress, school officials called off classes Monday after two second-floor classrooms of the brick Cypress Grade School were missing a roof and walls. They were looking for temporary shelter so students could finish the few weeks left in the school year.

The tiny town of Tobinsport sustained the heaviest damage in Indiana from the storms. A dozen people were injured and 10 of the 30 homes in the unincorporated community 60 miles east of Evansville were destroyed.

In Tennessee, a tornado cut a 10-mile path through the Murfreesboro area, about 30 miles southeast of Nashville, injuring 18 people and damaging 62 homes and buildings. Winds reached 140 mph.

A storm carrying heavy rains and winds exceeding 55 mph blew through Pennsylvania, dropping large hail, blowing the roofs off buildings and leaving thousands in the Pittsburgh area without power.

To the south, Charles County Sheriff Fred Davis said rescue workers went from home to home in La Plata, searching through rubble for people who might still be trapped.

Maj. Marc Bashoor, a spokesman for the Fire Department in neighboring Prince George’s County, said rescuers completed a second sweep through the wreckage early Monday morning to look for trapped residents. He said authorities were confident everyone in both counties was accounted for.

Shawn Murphy, who was delivering pizzas in La Plata when the tornado hit, described the funnel cloud as about 20-feet wide.

“It just started tearing up everything,” Murphy said.

In Missouri, Marble Hill was mourning the loss of Hoover, who until that night had been staying with his grandfather in nearby Grassy.

“The Lord just picked him out,” Bollinger County Sheriff Terry Wiseman said of the boy. “My chief deputy said it was the loneliest feeling he’d ever felt.”

“That was my first tornado, and if I don’t see another one, that’d be fine,” added coroner Charles Hutchings.