The morning incident involved a fake natural gas explosion and collapse of a 4-story building that trapped about 25 people in concrete and steel rubble. Responders, including firefighters, paramedics, HAZ-MAT teams, Urban Search and Rescue teams, structural engineers, ironworkers and victim search dogs, also had to deal with a pretend gas line erupting into a fireball with billowing smoke as they searched for victims.
About a mile away, a simulated chemical release trapped more than 20 mock victims at a plant requiring decontamination of victims and responders. The scenario continues Thursday evening when a medical helicopter crashes into a Boeing 757-300 jetliner at Midway Airport necessitating an emergency response to support the Chicago Fire Department.
Traffic around the South Side airport was to be detoured for four hours between 4 p.m. and 8 p.m. The drill ends a few hours later with a raid on terrorists at a mock biological weapons laboratory.
The simulations were designed to test emergency response systems to their limit.
Homeland Security Secretary Tom Ridge joined Mayor Richard Daley and Gov. Rod Blagojevich at the city's high-tech 911 Center to observe the exercises involving about 600 emergency responders and 125 vehicles mobilized under the statewide mutual aid plan signed into law six months before the Sept. 11, 2001, terror attacks on New York City and the Pentagon.
Meanwhile, emergency rooms at area hospitals remained overwhelmed for a third day by a stream of "patients" suffering flu-like symptoms after a mock bioterrorism attack. As of Wednesday, there were 1,676 mock cases of pneumonic plague with 366 deaths. The bacteria were released in three locations Saturday by a terror cell called GLODO.
Truckloads of fake pharmaceuticals and antibiotics were convoyed to distribution points in the city and suburbs after the shipment arrived at O'Hare International Airport Wednesday. Empty drug bottles were handed out to thousands of volunteers.
There is no vaccine for the disease but it can be treated with antibiotics within 24 hours of exposure.
A real traffic accident involving a semi-trailer truck on an overpass shut down two traffic lanes on Interstate 190 for two hours Wednesday, adding real-life drama to the disaster exercise.
"It had nothing to do with our thing but it was a stressing factor that added to the realism," said Larry Langford, spokesman for the Chicago Office of Emergency Management and Communication.
Officials said the drug distribution centers would have received the medications ahead of schedule despite the truck accident.
Law enforcement and government agencies will evaluate their performance Friday and on Monday top officials of the Department of Homeland Security in Washington will assess likely casualties and damages from nuclear, chemical and biological weapons attacks.
The Department of Homeland Security Wednesday allocated $700 million to increase security in urban areas and protect critical infrastructure. About $500 million in grants from the department's supplementary budget will go to the nation's 30 largest cities and metropolitan areas.
"One of the most important responsibilities of the Department of Homeland Security is to enhance the capabilities of our nation's first responders and first preventers who devote themselves to preventing terrorism and responding to emergencies," Ridge said.
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