UPDATE: The Bell County Fire Marshal released the cause of a fire early Wednesday morning at an aluminum manufacturing plant in Troy.

The fired started just after 3:30 a.m. at Anderton Castings, in the 200 block of Lely Dr. 

Steve Casey said an employee dropped a bottle of nitrogen into the molten metal, causing an explosion.

The explosion threw hot metal onto the ceiling of the building which caught fire and quickly spread throughout the building.

The building was a total loss.  The damage is estimated at $5-million.

Casey said six to eight people were in the building but no one was injured.  The man who caused the fire was wearing protective gear.

Firefighters from Troy and Temple were at the scene.  Casey said he expected they would be there all day Wednesday and possibly Thursday.

They were using large equipment to tear down the building so they can put out hot spots still burning inside the building.

Casey said the fire looked to be an accident and no criminal charges were expected.

Nikki Ramirez, a human resources representative for the company, said all hourly employees were told to stay home until further notice.  She said they could call her at 254-383-4019 if they had any questions.

According to the Anderton Castings website, the building was 142,000 square feet sitting on 30 acres of land. It was one of four Anderton facilities around the world, with other facilities in France, Mexico and Michigan.

The company markets itself as a leading supplier of aluminum chassis and powertrain components for the automotive, on- and off-highway and construction equipment.

The company was previously known as C & H Die Casting Inc.  It was cited by the Occupational Safety and Health Administration (OSHA) in 2013 and 2014 for major OSHA violations.