Update: Vehicle Explosion Possibly Result of High-speed Crash
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Mike Guenther, who witnessed the vehicle crash that caused the explosion at the U.S.-Canada border bridge, told NBC affiliate WGRZ: “So we were walking up the road and we seen this car coming down towards the border and he was flying over a hundred miles an hour, there was a car in front of him. He swerved out, went in front of the car, hit the fence, went flying up into the air. I think there was an elevation part. He went up into the air and we just seen the fireball and that’s all we could see. It was just covered in smoke everywhere.”

According to witnesses, the vehicle was traveling from New York toward Canada. Security camera footage obtained by NBC News appears to show the explosion was caused by the vehicle going into the air and crashing.