A fire at a Texas fertilizer plant led to a deadly explosion Wednesday evening at 8 p.m. local time that killed as many as 15 people and injured more than 170. The explosion tore through neighboring buildings and damaged 75 houses. First responders are conducting house-to-house searches with protective masks due to the threat of dangerous levels of ammonia fumes.

The ground motion from the explosion measured as a magnitude 2.1 earthquake, reported the U.S. Geological Survey, and the shock waves in the air would have been substantially higher.

At least six helicopters were dispatched to the scene to transport those with severe injuries to neighboring hospitals and a local football stadium was being used as a triage site. In Waco, nearly 20 miles south of the plant, more than 100 patients were being treated at Hillcrest Hospital for “blast injuries, orthopedic injuries (and) a lot of lacerations,” hospital CEO Glenn Robinson told CNN. Some 2,600 people in the community surrounding the plant have been evacuated, including many of the injured from a nursing home hit by the blast, Sgt. Patrick Swanton, public information officer of Waco Police Department told reporters Thursday morning.

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“What we are hearing is that there is one fertilizer tank that is still intact at the plant, and there are evacuations in place to make sure everyone gets away from the area safely in case of another explosion,” spokesman Ben Stratmann for Texas State Sen. Brian Birdwell told CNN. Though the fire was contained by early morning the fears that a second tank could explode remained.

D.L. Wilson, a state trooper with the Texas Department of Public Safety told reporters that the damage from the explosion reminded him of war scenes in Iraq and the 1995 Oklahoma City bombing. “I can tell you I was there, I walked through the blast area, I searched some houses earlier tonight. It was massive, just like Iraq, just like the Murrah building in Oklahoma City.”

A video posted on the New York Times blog site shows the fire just seconds before the explosion and the devastating force of the fireball.

IMAGE: With smoke rising in the distance, a law enforcement officer runs a check point at the perimeter about half a mile from the West Fertilizer Company April 18, 2013 in West, Texas. A massive explosion at the fertilizer company injured more than 100 people and left damaged buildings for blocks in every direction. The death toll from the blast, which occurred as firefighters were tackling a blaze, is as yet unknown. (Photo by Chip Somodevilla/Getty Images)