Fresno Fire is trying to determine the cause of an early morning fire that destroyed several storage units at a business in East Central Fresno.
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The call came in around 5:30 a.m. on Friday of a fire on Clovis near Shields.
The blaze ripped through 22 storage units at Clovis Avenue Self Storage.
When firefighters arrived they could see smoke and flames coming from several units. Fire officials say at one point ammunition started going off causing six minor explosions which changed their tactics.
"We had a lot of ladder pipes up with this fire, which means the ladder was pushing water down. But at the same time we also had our firefighters engaged in an aggressive offensive attack where it was appropriate," said Fresno Fire Chief Kerri Donis
Crews later found found guns and ammunition in one unit.
The cause of the fire is still under investigation and the extent of damage is unknown at this time.
Crews spent hours combing through the rubble to make sure the fire was out and so investigators can search for the cause.