One person is dead and Atlanta is under a state of emergency as the city picks up from the first downtown tornado in history.

The latest developments:

-- One person was killed and another injured in a house on Live Oak Road in Polk County, near the line with Floyd County, Polk County 911 director Thomas Wilson told the AJC at 2:30 p.m. The victims have not been identified because their relatives have not been notified. Earlier reports had indicated two deaths.
The latest developments:

-- A tornado warning is in effect for southeast Cherokee, Forsyth, Hall and northeast Fulton counties until 3:15 p.m.

-- State Insurance Commissioner John Oxendine says the damage could be as high as $150 million, according to preliminary estimates. He said the bulk of that damage occurred at the Georgia World Congress Center, where windows were shattered, seats were scattered and portions of the ceiling sustained major damage.

"There is not a building that is safe" at the Georgia World Congress Center, Oxendine said.

-- At a noon news conference, Mayor Shirley Franklin declared a state of emergency and requested that Gov. Sonny Perdue provide disaster assistance. The city will be working with Georgia Emergency Management Agency, as well as FEMA.

-- Much of north Georgia, including metro Atlanta, is under a tornado watch until 7 p.m., the National Weather Service said late this morning.

-- Early this afternoon, authorities were advising people to stay out of four areas of the city: downtown, Vine City, Cabbagetown and the Cotton Mill lofts. An additional 125 officers will be patrolling those areas for the next 18 hours.

"It is important for the public to stay at home," Franklin said. "Do not use this as an opportunity for sightseeing."

-- The Red Cross is placing displaced residents at two locations: Helene Mills recreation center and the Central Park recreation center. The agency moved at least 70 people from Helene Mills to extended stay hotels.

-- As of noon, as the city braced for the next storm, 10,000 Georgia Power customers were without power. Crews repaired downed lines and poles throughout the night, with 30,000 losing power at some point. The peak outage was 19,000.
If the new storms are strong, the company said it will have its linemen stand down until it passes, to protect their safety. "We're monitoring the situation, as you might imagine," said spokesman Jason Cuevas. "If it looks like it's going to be severe, we'll pull them."

-- Atlanta Fire Chief Kelvin Cochran reported 30 injuries following Friday's storms; none were serious. The injured included one firefighter who suffered an ankle injury.

-- Friday night's tornado was declared a category EF2, with the strongest winds reaching 135 mph. Tornadoes can reach up to a category EF5 with 300 mph winds. The tornado was 200 yards wide at its widest. It left a path of damage six miles long, said meteorologist Mike Griesinger with the National Weather Service.

-- Friday's twister touched down near the World Congress center, the Omni, Philips Arena, the Equitable Building, and then across to Cabbagetown. The twister is the first to hit downtown Atlanta since such weather recording-keeping began in the 1880s, Griesinger said.

-- Damage was sufficient. At Centennial Olympic Park, two of the 65-foot tall "Hermes Towers" that resemble giant Olympic torches were blown down. The Georgia World Congress Center reported widespread damage, including to its roof. Even a downtown Atlanta penthouse belonging to Ted Turner suffered damage. The familiar bison-shaped sign outside his Ted's Montana Grill restaurant will need to be replaced.

-- The tornado may have seemed to strike Atlanta with no warning, but that's not true. The weather service issued a tornado warning about 12 minutes before the twister touched down in the city, Griesinger said. "There was a warning," he said.

He said 12 minutes is about an average amount of time for a tornado warning. The warnings are sent out to local TV stations, weather radios, emergency management offices and cell phones programed to receive weather alerts. The TV stations typically air such warnings almost instantaneously, he said.

Shortly before 10 p.m., winds whirled through downtown Atlanta, taking aim at CNN Center, the Omni Hotel and the Georgia Dome, which was packed with thousands of Southeastern Conference basketball fans.

The bulk of the storm's wrath fell on the core of the city.

Sections of the Georgia Dome's roof were ripped off, forcing officials to move the four remaining games in the SEC tournament -- three today and one on Sunday -- to Georgia Tech's Alexander Memorial Coliseum. Ticket holders will not be allowed in the arena. The first of three games today -- Georgia-Kentucky -- tipped off at noon.

Access to the remaining games of the tournament will be limited to athletes' family members, cheerleaders, bands and other individuals with credentials, the SEC announced.

Officials from the SEC, the schools remaining in the tourney and the Dome deliberated from midnight to roughly 4 a.m. Saturday before announcing a new schedule and ticket policy. Alexander seats 9,191 fans, much fewer than the 25,000 the Dome holds.

During the brief storm, a vacant two-story commercial building across from Centennial Olympic Park came down.

Massive pieces of metal siding peeled off a Marietta Street parking garage and wrapped around poles or clogged sidewalks and streets.

"I have not seen anything like this before," Atlanta fire Battalion Chief Gerry Rusinski said. "It looked like 9-11 when we pulled up."

Four area hospitals, including Grady Memorial Hospital and Atlanta Medical Center, reported taking in 16 patients from Friday's storm -- most with minor injuries, though one reportedly in critical condition.

The same strong winds that sent patients to Grady also damaged buildings and ambulances there, officials said Saturday.

Among the hardest hit communities Friday was Cabbagetown, where this morning about 50 search-and-rescue team members worked on three areas of Stacks Lofts (170 Boulevard), which had collapsed. Large chunks of four floors collapsed on top of each other like a pancake.

The hunt for possible survivors or bodies could take up to 36 hours, Atlanta fire Capt. Bill May said Saturday morning.

Sandy Smith of Douglasville was at the SEC tournament game when the storm hit. The Alabama-Mississippi State quarterfinal game had gone into overtime when she heard a loud boom.

The ceiling started waving like a sheet. "The lights started moving and the TV monitor started swaying back and forth," she said. Then a pole and sign tore a hole in the roof.

Outside, windows popped and shattered at the Omni Hotel. A billboard across from Olympic Park fell onto a car. Newspaper stands dropped in rows like dominos on sidewalks. Trees were pulled from the ground.

Darryll Douthard, 42, a valet parking attendant for the Thrive restaurant on Marietta Street, said one man drove into the parking garage as the storm hit.
As Douthard rushed him in a rear door, the man resisted, worrying about his car.
"Are you concerned with your car or your life? Douthard asked. "Get in the staircase!"

Marietta Street, deserted Saturday, turned into a sea of bodies hours before -- many of them in basketball jerseys. Some were crying and visibly shaken.
Other than an Easter egg hunt at the Governor's mansion, most of Saturday's activities were scratched.

Philips Arena reported no damage but called off its "Winter Jam Spectacular" concert. The downtown St. Patrick's Day parade was canceled. And thousands of attendees were turned away Saturday morning from the Georgia World Congress Center, site of the Thomas P. Hinman Dental Meeting.
Several were still shaken from Friday night's trauma.

"The wind just kept getting faster and faster and louder and louder," said dentist Doug Clepper of Augusta. He and his wife took the fire escape downstairs from their 10th floor room in Omni Hotel.

"It was very surreal. People were dressed up for parties. Women were crying."

-- Rhonda Cook, Tim Eberly, Margaret Newkirk, Chandler Brown, Chip Towers, Craig Schneider, Phil Gast, Paul Shea, Paul Kasko, Gayle White, Michelle Shaw, Mike Knobler, Anisha Frizzell, Ben Smith, Andy Miller and Celine Bufkin contributed to this article.