MEAD, Colo. -- A Boulder Scientific employee who suffered severe burns in an explosion and fire at the chemical plant in Mead died from his injuries Friday.

He was identified as Leslie Robertson, 37, of Loveland, Colo.

Robertson was working near an oven where they cook the chemicals when the explosion occurred, said a spokesman with Mountain View Fire.

Robertson was airlifted to University Hospital in Denver with third-degree burns to his head, face, arms, chest and back. Doctors were not able to save him and he was pronounced dead at 11:30 a.m.

Robertson was an assistant supervisor who has worked for Boulder Scientific for 10 years, the company said.

The incident occurred at about 6:55 a.m. Neighbors living across the street from the plant said they heard a loud boom, saw a large plume of dark smoke and then heard the sirens.

"Upon our arrival, there was a small fire and we were able to quickly extinguish it," said Steven Pischke, of Mountain View Fire. He said the fire suppression equipment in the plant -- the sprinkler system -- helped keep the fire from spreading.

Pischke said there was no chemical release into the air as a result of the explosion, which resulted in a large plume of smoke that could be seen for miles.

The damage was limited to one building, but the plant shut down operations as precaution.

The cause remains under investigation. The Occupational Safety and Health Administration has two investigators at the scene.

"They have excellent fire supression system. This is a safe plant. They follow code," said Jesse Hodgson, public information officer for Mountain View Fire.

Hodgson said residents should not worry about their safety.

But some neighbors don't feel relieved.

"I don't like it at all," said Jamie Riley. "I don't know if it's poisoning us here."

"Boulder Scientific has an impeccable safety team and measures in place to deal with any fires, spills or releases. They worked exactly as they should have this morning," Hodgson said. "Many suppression systems in most businesses would be overwhelmed with a 10 gallon gasoline fire. Boulder Scientific has a superior system, and when tested, proved that this morning."

Three people were injured in an explosion at the same plant on March 14, 2007.

"Years ago, I can't remember how many exactly, there was an explosion at Boulder Scientific and they evacuated the whole town at that time," said Margaret Cornell, a resident who has lived in the area for 42 years. "It's scary down there. Nobody knows in town what that plant is."

"There's a school right down the street from there, you know. My kids play out here all the time. I think we all need to know what's going on in there and if it's safe or not," said resident Scott Burch. "I don't think it belongs in the middle of town, it should be out in the middle of nowhere."

But Michael Benson he feels secure. "We researched this place for a couple of years before we moved here," he said.

And Kalyn Diede, who recorded the smoke plume with his cell phone, said "Nothing major has happened in the time that I've lived here."

Mountain View fire officials say Boulder Scientific performs a variety of tests on various chemicals to see if they can mix or match them.

The chemical manufacturing company employs about 100 people. The company was fined $1,925 in May 2007 following a fire, according to Herb Gibson, area director for OSHA. The fine was for a chemical leak that was not contained.

"That fine was reduced at settlement," said Gibson.

Dan Morrison, the director of business development at Boulder Scientific, released the following statement to 7NEWS:

Currently, the source of the incident is unknown. Boulder Scientific Company, in conjunction with the Mountain View Fire Department and the Federal Occupational Safety and Health Administration (OSHA), are conducting a thorough investigation to determine the cause of the incident. Boulder Scientific Company will fully cooperate with the on-going investigations.

We are deeply saddened by the loss of Les, and our heart-felt sympathy goes to all of his family and friends for their loss. Counselors are working with Boulder Scientific Company employees to help them cope with their grief with the loss of their friend and co-worker of so many years. Les will be deeply missed by many.

The plant is closed while the investigation continues.

Read more about Boulder Scientific on their Web site.