Explosion hits fertilizer plant north of Waco, Texas

(CNN) -- An explosion ripped through a fertilizer plant Wednesday night in the town of West, Texas, sending a massive fireball into the sky and causing dozens of injuries, officials said.

A hospital in nearby Waco, Texas, has been told to anticipate 100 injured people coming in from the fertilizer plant area, an official at the medical facility said.

Glenn Robinson, CEO of Hillcrest Hospital, said a field triage station was being set up on a football field near the plant some 18 miles north of Waco after the Wednesday night explosion.

"We have had a steady flow of patients coming in by ambulance as well as by private vehicles," Robinson told CNN's Anderson Cooper. He said more than a dozen injured people had been brought in by ambulances and "more than 20 -- that number is continuing to climb -- by private vehicle."

Hazardous material teams were being rushed to the scene, an emergency management official said.

At least six helicopters are going to fly out those who are injured, Robinson said. Others are being transported by ambulance, and some are getting to the hospital by car, he added.

Two other hospitals in the region were also assisting.

Photos of the explosion -- which reportedly happened around 7:50 p.m. (8:50 p.m. ET) -- showed a huge blaze and flames leaping over the roof of a structure and a plume of smoke rising high into the air.

The West Fertilizer Plant is just north of Waco. A school and a nursing home are among the buildings near the plant, CNN affiliate KWTX reported.

Sen. Brian Birdwell said he was aware of the explosion and trying to get more information, a spokesman said.

"I stand ready to assist with any and all state resources that might aid the affected area," Birdwell said in a written statement.

Texas Gov. Rick Perry is also aware of the explosion, a spokesman said, and was working to get resources into the area.

Tommy Alford, who works in a convenience store about three miles from the plant, told CNN that several volunteer firefighters were at the store when they spotted smoke. Alford said the firefighters headed toward the scene and then between five and 10 minutes later, he heard a massive explosion.

"It was massive; it was intense," Alford said.