CORPUS CHRISTI, Texas (AP) – Two of the seven workers injured when a storage tank at a petroleum facility in Texas exploded after catching fire were released from the hospital, while the remaining five are hospitalized in stable condition, officials said Sunday.

Corpus Christi Fire Department Deputy Chief Richie Quintero said Sunday that the cause of the explosion remains under investigation.

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The seven employees of Shelton Services Inc. were cleaning an aboveground storage tank at Magellan Midstream Partners’ Corpus Christi petroleum facility when the fire happened Saturday, Shelton Services said.

Shelton Services said Sunday that two of the employees were released from a Corpus Christi hospital on Saturday while five others are in stable condition at Brooke Army Medical Center in San Antonio.

Quintero has said that a shelter in place order that was issued after the blast was lifted shortly before noon Saturday, and there were no other injuries or property damage and no air contamination. The fire was extinguished and firefighters had left the site by early Saturday afternoon.

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Mark Calhoun, operations manager for Magellan Midstream Partners, has said the Magellan plant has 60 storage tanks and a small refinery that was not affected by the blast.

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