CRESSON, Texas (CBSDFW.COM/AP) – The girlfriend of the man who is missing and presumed dead after an explosion at a Texas chemical plant says she keeps calling his phone, hoping he’ll answer or that the rescuers will hear it and find him.

Amber Gutierrez, Dylan Mitchell’s girlfriend, was waiting Friday afternoon near the site of Thursday’s explosion at a Tri-Chem Industries plant in Cresson, 50 miles southwest of Dallas. Mitchell’s brother and cousin waited with her.

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Gutierrez says Mitchell moved with the company from their Arlington warehouse when they opened the plant about a year ago in Cresson.

She said he was a he was a jack-of-all-trades. She says, “He did everything around here. He gave his life to this place — literally.”

Dylan Mitchell (Mitchell family)

Two other workers were injured in the explosion. One has been released from the hospital while the other remains in serious condition.

The search has been hindered by fire at the plant and hazardous chemicals.

The Environmental Protection Agency as well as a hazmat team were at the Tri-Chem Industrial plant throughout the day making sure what left the chemical plant is safe enough for rescuers to go inside to search for Dylan Mitchell. He is the only one of 12 plant employees who is unaccounted for after Thursday morning’s explosion.

“We had multiple explosions in the building while the fire was taking place,” said Hood County fire marshal Ray Wilson.

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Hood County plant explosion (Chopper11)

Mitchell’s brother says Dylan’s co-workers saw him kick a lid, causing sparks in the moments before the blast. At least six searches for the 27-year-old came up empty.

Investigators flew a drone over the building for several hours Friday.

The images will be used to build a 3-D map of the blast site. The one part of the building rescuers haven’t searched is where the roof collapsed.

“The Cresson Fire Department did try to make an initial entry into building before it collapsed but were pushed out by those explosions,” said Wilson.

Two other men were also hurt in the explosion. Hours ago, the sister of the missing Dylan Mitchell posted a message on Facebook, saying her heart hurts and she can’t imagine life without him.

Authorities also tell us the EPA continues to test air quality to make sure it’s safe. So far, the air has been determined to be safe.

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