Doyle Rice and Larry Copeland, USA TODAY
A violent storm system pounded the Midwest on Sunday with tornadoes, strong winds and heavy rain, killing at least six people, injuring dozens and collapsing homes and other buildings.
National Weather Service officials confirmed that several tornadoes touched down in Illinois, Indiana and Kentucky.
The White House said President Obama had been briefed on the damage and was receiving regular updates. The Federal Emergency Management Agency said it had sent emergency teams and liaisons into affected states.
"Residents should continue to monitor weather conditions as they develop and follow the direction of local officials," FEMA Administrator Craig Fugate said. "Be prepared for power outages and dangerous road conditions as a result of downed power lines and flooding.''
Two people were killed when a storm, believed to be a tornado, struck a rural part of Massac County near Brookport, Ill., said Larry Douglas of the county's emergency services and disaster agency. No further details were available.
Washington County Coroner Mark Styninger said an elderly man and his sister died Sunday afternoon when a tornado hit their farmhouse in the town of New Minden, Ill., about 50 miles southeast of St. Louis.
Another person was killed in Nashville, Ill., said Patti Thompson, spokeswoman for the Illinois Emergency Management Agency.
"The whole neighborhood's gone. The wall of my fireplace is all that is left of my house," said Michael Perdun of Washington, Ill., a town of 16,000 about 140 miles southwest of Chicago. He said his neighborhood was wiped out in a matter of seconds.
Illinois State Police Trooper Dustin Pierce said the tornado cut a path from one end of Washington to the other, knocking down power lines, uprooting trees and rupturing gas lines.
Washington Alderman Tyler Gee told Chicago station WLS-TV that destruction was so great "I couldn't even tell what street I was on." He said hundreds of homes were "just completely flattened.''
Just how many tornadoes hit was unclear. According to the National Weather Service's website, a total of 65 tornadoes struck, most of them in Illinois. But meteorologist Matt Friedlein said the total might fall because emergency workers, tornado spotters and others often report the same tornado.
In Indianapolis, a historic post office, built in 1903, was demolished by strong winds and heavy rains.
"We had just acquired the building in December and taken out all the interior of the building, gutted it and solidified the structure a little bit," said Megan Bennett, a volunteer with the Irvington Development Organization. "Then bad weather comes along and blows it down. The reinforcement steel was set to be delivered tomorrow, so it's really heartbreaking."
A tornado hit near East Peoria in central Illinois, where photos from the area showed devastating damage.
"There are reports of significant damage in the towns of Washington and Pekin, Ill.," Thompson said. "There's been a wide disruption of communications in those areas also. We have dispatched staff and communications equipment to help support the local authorities. There are reports of people trapped (in collapsed buildings), and technical rescue teams have been dispatched.
"It's a pretty widespread event here in Illinois," Thompson said.
She did not have specifics on how many people were injured or on damages from the storms. Officials had opened a shelter in the Washington area, and the state's Emergency Operations Center had been activated.
Significant storm damage also was reported in Coal City in Grundy County, and in LaSalle County.
Heavy winds knocked out power to 140,000 customers in Michigan, including in the Detroit area.
The weather service had confirmed at least four tornadoes in Indiana by midafternoon, as central Indiana remained under a tornado watch until 8 p.m. The storms left at least 13,000 people across Indiana without power, according to Duke Energy.
"This is a very dangerous situation," Russell Schneider, director of the National Weather Service's Storm Prediction Center, told the Associated Press at midday Sunday. "Approximately 53 million in 10 states are at significant risk for thunderstorms and tornadoes."
Heavy rain and lightning in Chicago delayed the NFL game between the Baltimore Ravens and Chicago Bears at Soldier Field, but the weather had not caused any major emergencies in the city.
Severe weather forced play to be stopped and fans were evacuated from the field seating bowl with 4:51 remaining in the first quarter of the game.
The initial evacuation came at 1:31 p.m. ET. Five minutes later, referee Gene Steratore announced play would be "temporarily suspended" and both teams left the field. The game was restarted after a nearly two-hour delay.
Once the storm passed, the sun came out, giving some residents along the Chicago lakefront views of spectacular rainbows.
FOOTBALL IMPACT:Bears-Ravens game in Chicago 'temporarily suspended'
In Peoria, OSF Saint Francis Medical Center, treated 24 tornado victims Sunday evening for injuries ranging from head wounds and broken bones to cuts and bruises, said hospital spokeswoman Kristen Johnson. Six of the wounded were trauma patients, meaning they were the most severely injured, she said.
Eight to 10 people were treated at and released from UnityPoint Health-Methodist Hospital, also in Peoria, hospital spokesman Duane Funk said.
Earlier Sunday, the National Weather Service issued a "high risk" alert of severe weather for eastern Illinois, Indiana, western Ohio and far southwest lower Michigan, with conditions favorable for a tornado outbreak and widespread damaging winds.
This is the first time in decades that a "high risk" area was issued so far north in the month of November, according to meteorologist Jeff Masters of the Weather Underground.
The agency says strong winds and atmospheric instability are expected to sweep across the central Plains during the day before pushing into the Mid-Atlantic states and Northeast by evening. The potential for strong and long-track tornadoes will continue in the Ohio Valley and adjacent Midwestern states.
The storms are expected to diminish in intensity Monday, but strong wind gusts will remain possible for parts of New York, Pennsylvania, Maryland and New Jersey, according to the Weather Channel.
Contributing: Katherine Lackey in McLean, Va., William M. Welch in Los Angeles, William Spain in Chicago, The Associated Press, The Indianapolis Star