( CNN ) -- A mushroom cloud of thick dark smoke hovered over the Puerto Rican capital after a blast ripped through a fuel storage complex near San Juan early Friday and caused a massive fire . At least one injury occurred and at least 350 people have been evacuated as about 100 firefighters worked through the night to fight the blaze , Gov . Luis Fortuno said . Firefighters said it would take a few days to control the inferno . Eleven tanks are ablaze , and firefighters are trying to cool down the remaining 29 tanks . The tanks are holding jet and diesel fuels and gasoline . Authorities are looking into the cause of the blaze , which took place at Caribbean Petroleum Corp. , a storage complex on San Juan 's bay that owns the Gulf brand in Puerto Rico . iReport.com : See , share , send images of the explosion . Justin Gehrke , a U.S. Army civilian employee who filed an iReport for CNN , was taken aback by the sight of the thick black smoke and took photos of the scene from his iPhone . `` I did n't expect to see a mushroom cloud from my house , '' he said .
Explosion , fire rip through fuel storage complex . One person injured , 350 evacuated near San Juan , Puerto Rico . Caribbean Petroleum Corp. tanks held jet , diesel fuels plus gasoline . iReport.com : Are you there ? Send photos , videos of the flames .