Ensimmäinen räjähdys tuotti harmaan räjähdyspilven, joka on tyypillistä ilotuliteruudille
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But the compound itself typically doesn't detonate on its own and requires another ignition source. That likely came from a fire that engulfed what initially appeared to be fireworks that were stored at the port.
Online videos of the disaster's initial moments show sparks and lights inside the smoke rising from the blaze, just prior to the massive blast. That likely indicates that fireworks were involved, said Boaz Hayoun, owner of the Tamar Group, an Israeli firm that works closely with the Israeli government on safety and certification issues involving explosives.
"Before the big explosion, you can see in the center of the fire, you can see sparks, you can hear sounds like popcorn and you can hear whistles," Hayoun told The Associated Press. "This is very specific behavior of fireworks, the visuals, the sounds and the transformation from a slow burn to a massive explosion."
Jeffrey Lewis, a missile expert at the Middlebury Institute of International Studies in Monterey, California, offered a similar assessment.
"It looks like an accident," Lewis told the AP. "First, there was a fire preceding the explosion, which is not an attack. And some of the videos show munitions what I could call popcorning, exploding like 'pop, pop, pop, pop.'"
He added that "it's very common to see fires detonate explosives."
"If you have a fire raging next to something explosive, and you don't put it out, it blows up," he said.
The move comes amid speculation that negligence was to blame for the explosion that killed at least 135 people.
abc7chicago.com