PETERSBURG, IND., JUNE 3 -- Midwesterners mourning neighbors killed in a deadly barrage of tornadoes were hit today by a second onslaught of thunderstorms and high winds that raised the weekend weather death toll to 13.

Wind-toppled trees killed a female camper in Wisconsin and a young boy in a town park in Indiana, the state that bore the brunt of the fierce weather that began Saturday night.

Across Indiana, officials reported that eight were killed and at least 150 people injured Saturday in the state's worst tornado outbreak since 1974. The storms left 24 cities in 15 counties with significant damage. Officials tracked about 50 tornado touchdowns during a four-hour period.

In Illinois, a tornado Saturday destroyed or damaged scores of houses and killed one woman. Also Saturday, 10-year-old boy drowned in a storm-swollen river in Milwaukee and an 82-year-old man was killed by a wind-blown tree branch in the northwestern Missouri town of Stewartsville.

Twisters or tornado-force winds downed trees, knocked out power and damaged homes and businesses from Kansas to Michigan and Ohio. In Arkansas, thunderstorms dumped heavy rain, causing flash flooding that closed roads.

In the second round of deadly weather today, high winds at a campground in Rocky Arbor State Park in south-central Wisconsin toppled a tree onto a tent, killing one woman and injuring another, according to the Juneau County Sheriff's Department.

In the central Indiana town of Mulberry, a 60-foot-tall tree blew down, striking three children at a picnic, said Town Marshal Bruce Welton. All were younger than 10 years old, he said.

At least 150 homes and 18 businesses in Petersburg were destroyed and 120 homes and 58 businesses damaged when the storm ripped a five-mile path through town, said Al Miller, field operations coordinator for the Indiana State Emergency Management Agency. At least 57 people were injured.

"The tornado clearly cut right through the middle of town," said Gov. Evan Bayh, declaring a state of emergency. "It looked to me like there had been a bombing run made right through the middle of Petersburg."

Residents of the mining and farming community of 3,000 in southwestern Indiana had been without fresh water for two weeks because of floods that tore through levees along the White River and severed the water main.

Jerome Hauer, director of the State Emergency Management Agency, said the tornadoes were particularly devastating because they spent long periods on the ground. One twister, he said, was on the ground 38 minutes: 10 minutes in Illinois and 28 minutes in Indiana.

Mary Hall, 63, picked through the rubble of her collapsed home early today. She and her husband, Clifton, took cover in the basement porch when the storm hit. "The insurance man told us to save what we could, but there's really nothing left."

Indiana National Guard troops and state police patrolled streets and roadblocks on the edge of town kept the curious away.

In Illinois, Jasper County was hardest hit, with 30 homes destroyed and at least 70 damaged, while Shelby County reported 12 homes demolished and 26 others damaged. The only death in the state, however, was reported in Edwards County, where a 54-year-old woman died when the twister destroyed her home.

"It's just total devastation," Edwards County Coroner Mark Curtis said. "It's unbelievable. Everything they tell you about tornadoes -- the roar like a train, the wind -- is true."

Elsewhere over the weekend:

In Wisconsin, several thousand residents of Fond du Lac, an eastern Wisconsin city of 36,000, were temporarily without electric service as tree limbs tore down transmission lines. In Milwaukee, searchers today found the body of a boy, 10, who slipped into the Menomonee River shortly after storms swept through the area the previous evening.

In Ohio, a tornado damaged 100 houses and 50 businesses in Harrison, outside Cincinnati, police Sgt. Carl Butler said. No serious injuries were reported.

In Kentucky, tornadoes hit several counties, damaging houses, tossing mobile homes, downing trees and cutting power. At least five people were injured, none seriously.

In Michigan, a tornado touched down in Big Prairie Township, damaging vacation trailers. No injuries were reported.