Two tornadoes swept through south-central Missouri Friday afternoon, damaging more than 100 homes and tearing off part of a roof at a middle school moments after a tornado drill. No deaths had been reported.

A firefighter videotaped two twisters moving through the town, said Phelps County emergency management director Bruce Southard. He estimated the tornadoes were on the ground for about 10 minutes.

"It's devastating," he said. "We've got nice houses that are just tore to pieces."

Twelve-year-old Devin Wilburn said students at St. James Middle School had just completed a tornado drill. Thirty seconds later, they interrupted their science test to rush back into the hallway for the real thing. The children knelt down and put their hands over their heads, he said.

"I just heard a bunch of thunder and ripping, because the top of the roof came off," Devin said.

No teachers, children or staff members were injured.

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Preliminary information indicates a tornado warning was issued about 30 minutes before the storm hit, said Gino Izzi, a meteorologist with the National Weather Service in Springfield.

A tornado also destroyed about half of the Manchester Packaging Co. plant, which makes polyethylene film and bags, according to its Web site. Southard said the twister ripped 70-foot-by-70-foot holes in the main building of a Wal-Mart distribution center and another Wal-Mart building used to service trucks.

Devin's father, Chuck Wilburn, was sleeping when he was awakened by a "roaring wind noise." Wilburn, 42, said he ran to let the dogs in from outside.

"I opened the door and saw the barbecue grill flying across the yard," Wilburn said, whose house lost a window and some siding.

Southard estimated between 100 and 125 homes were damaged. He said most the damage was to roofs but some porches also collapsed.

The storm also ripped down trees, blocking traffic and leaving about half the city of about 6,000 people without power. St. James is 86 miles southwest of St. Louis.

Authorities also reported that two other small tornadoes downed trees and took off shingles in rural parts of southeast Missouri. Tornadoes and hail were also reported in northern Arkansas.

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