Transcript for Massive explosion at a silicone plant in Illinois
Next to the disaster zone in northeastern Illinois. That massive explosion at a silicone plant, shaking the ground. You see the moment right there on surveillance video. At least one worker killed. Several hurt, and officials now fearing the worst for those still missing in the wreckage. ABC's Zachary kiesch with that tonight. Reporter: The sudden explosion rocked this Illinois chemical plant, leaving it unrecognizable. Flames shot in the air as emergency crews raced to the scene. Dozens of firefighters battled the blaze on the ground and from ladders above. Very, very loud explosions coming from the area. 10-4, it did shake our building, multiple 911's. Reporter: Debris sent flying for blocks, but the blast was felt miles away. All of a sudden my lights flickered and then I heard this really loud explosion, and the whole building shook. Reporter: This surveillance video shows the moment of the explosion, and that rattling aftershock. Officials say it happened around 9:30 Friday night, cleaning crews had just left for the night but there were a handful of people inside. Daylight revealing the utter devastate. At least one person found dead. Two more are missing. Four have been hospitalized. The plant, 40 miles outside of Chicago, manufactures silicone. Officials say there were no warning signs of imminent the search stopped today when the site was deemed too unstable and dangerous to work. Every one of those with the piping overhead has been damaged from the structure, and it's hanging somewhat insecurely, and doesn't allow us to operate safely. Reporter: Authorities testing the air quality for toxins and finding no safety threat. Tom, investigators haven't been able to determine a cause, but until that scene is considered safe, they won't be able to get inside that building to determine what triggered this deadly blast. Tom? Zachary kiesch, thank you. Now to the major headline overseas. The surprise launch from north
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