PHOENIX -- Investigators are trying to determine if Thursday night's storm sparked two separate fires that started at about the same time at a pair of Phoenix businesses located in the same area.
More than 150 firefighters were called out to the area of 39th Avenue and Indian School Road, which is an industrial area.
One of the businesses that burned is called Bandolero Molding. It's sandwiched between an appliance company and another business.
The other fire was at a nearby business that had tires and wood pallets. Toxic smoke was coming off of that fire. No evacuations were necessary, but fire officials warned people to avoid the area until the smoke cleared.
Investigators were still on scene Friday evening, after a business owner who was assessing the damage discovered what he believed to be explosive devices among the burned debris.
"I saw what looked like, to me, a bomb," said Hawzin Ali, whose auto shop was seriously damaged by fire. "I'm from north of Iraq ... so yes, I have seen it many times before. When I called 911, I tried to explain it to them. They asked me what it looked like. I said, you know, to me, it looks like a big bullet."
The Phoenix Police Department Bomb Squad; the Bureau of Alcohol, Tobacco, Firearms and Explosives; and bomb experts from Luke Air Force Base responded.
Investigators found dozens of tubes for explosive ordnance, but only two live munitions, according to Phoenix police spokesman Officer James Holmes. Authorities believe there was a third military-grade explosive that went off Thursday night.
Evacuations and road closures were put in place.
"There was hundreds of first responders out here -- firefighters, medical personnel, law enforcement -- that were in immediate danger, and they didn't know it because they were dealing with this blaze," Holmes said.
Investigators are trying to determine whom the devices belonged to and how they ended up there. Holmes said Friday evening that police could be on scene for another 24 hours.
Holmes said there is no lawful reason why a person would have these kinds of explosives. He said it appears they were purchased via military surplus, and the person who bought them may not have known three actually contained live munitions.
"It's really dangerous," Ali said. "I'm more concerned ... where this material came from."
The explosives were retained by the Luke Air Force Base Explosive Ordnance Disposal Squadron. The ordnance has not officially been identified, according to Holmes.
A watchdog was killed but no people were injured.
Investigators have not determined what sparked the fire, but they are not ruling anything out. The initial thought was that lightning or a downed power line might be to blame, but they have not confirmed that at this point.
Police probe explosives found at fire scene
PHOENIX (AP) -- Police were investigating Saturday the discovery of military-grade explosives in the rubble of a burned structure that was among several buildings destroyed in two separate blazes that broke out in an industrial area of west Phoenix.
The fires started Thursday night as the city was hit with the first dust storm of the summer monsoon season that brought rain, lightning and powerful winds gusting up to 50 mph.
It was not immediately clear what caused the fires, but authorities were looking into lightning as a factor.
As firefighters worked to put out the blazes, an explosion occurred inside one of the structures, Phoenix police Officer James Holmes said. No injuries were reported, he said.
But an investigative team later found dozens of tubes used for explosive devices at one of the sites, with several of them containing live munitions, Holmes said. Members of the Luke Air Force Base Explosive Ordnance Disposal Squadron have since retrieved the devices, he said.
The investigation was continuing while authorities worked to determine exactly what the explosives were made of and who they belonged to.
"It appears at this point a person may have purchased the cases via military surplus and may not have known three actually contained live munitions," Holmes said.
The fire started at an appliance store before spreading to several surrounding structures.
Business owner Luis Torres said his 9-year-old pit bull died in the blaze while serving as a guard dog on the property.
"It's actually devastating because we had our buddy Duke that we actually lost last night," Torres told the television station. "Actually one of our best friends, our dog."
Torres estimated he lost about $500,000 in property, but he said his company was insured.
"It's like they say, it's an act of God," he said. "What can we do? Nothing. Just go with it."
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