BIRMINGHAM, Ala. – Apparent tornadoes destroyed houses, sent people to hospitals and tore up the roof of a maximum security prison in northern Alabama as bad weather threatened more twisters across the region Friday, two days after a storm system killed 13 people in the Midwest and South.

Anxiety mounted from Georgia to southern Ohio across a wide swath where forecasters said severe weather could hit later in the day. Thousands of schoolchildren in several states were sent home as a precaution. Meanwhile, residents in parts of Illinois hit hard by storms earlier in the week salvaged what they could from damaged homes.

In the Huntsville area, at least four people were taken to area hospitals, and several houses were leveled by what authorities believed were tornadoes Friday morning. The extent of the people's injuries wasn't immediately known, and emergency crews were continuing to survey damaged areas. WAFF-TV aired video of crushed homes.

An apparent tornado also damaged a state maximum security prison about 10 miles from Huntsville, but no inmates escaped. Alabama Department of Corrections spokesman Brian Corbett said there were no reports of injuries, but the roof was damaged on two large prison dormitories that each hold about 250 men.

"It was reported you could see the sky through the roof of one of them," Corbette said.

A portion of the prison fence was knocked down, but the prison was secure, he said.

The Limestone Correctional Facility in Capshaw houses more than 2,100 inmates, including more than 200 inmates who have tested positive for HIV and are segregated. The perimeter fence surrounds 90 acres of the prison that opened in 1984. Farming and cattle operations lie elsewhere on the sprawling 1,600-acre grounds owned by the prison, according to state Department of Corrections.

Authorities are confident that storms that hit Limestone and Madison counties were tornadoes, but it will be up to the National Weather Service to confirm the twisters, said Alabama State Emergency Management Agency spokeswoman Yasamie August.

"We're still getting reports of damage pretty much as we speak," she said at midday.

Forecasters warned of severe thunderstorms with the threat of tornadoes crossing a region from southern Ohio through much of Kentucky into Tennessee, Alabama and Georgia.

Schools sent students home early or canceled classes entirely in states including Alabama, Tennessee, Mississippi and Kentucky. In Alabama alone, more than 20 school systems say they are dismissing classes early Friday because of the possibility of severe storms. Otherwise, the bad weather could hit around the time schools normally dismiss for the day, based on predictions from the National Weather Service.

Residents were picking through debris in parts of Illinois that were devastated by the previous round of severe weather on Wednesday. The 9,000-resident town of Harrisburg was sacked by a twister about 5 a.m. Wednesday that killed six people. Forecasters weren't expecting the area to be hit hard by the newest storms, though.

The forecast in Harrisburg didn't much matter to Amanda Patrick, who lost her home Wednesday in the same twister that killed her neighbors in the area where most of the fatalities occurred.

"I don't know what to tell you other than I take it one moment, one day at a time," Patrick, 31, said a day after riding out the storm in the bathtub she barely was able to crawl into for shelter before the twister hit.

She considers herself blessed, having thought the sirens that wailed as the tornado barreled down on her neighborhood was actually part of her dream. She awakened just minutes before the tornado hit and hours later couldn't stop sobbing over the neighbors she lost.

"I'm not crying as much now. I'm here right now, standing," she said Thursday. "Now, I will get up every time I hear a siren."

• Associated Press writers Jim Suhr in Harrisburg, Ill., and Jeff Martin in Atlanta contributed to this report.

• WAFF-TV

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