UPDATE: Thursday, April 18, 7:15 a.m.
Police in Texas say between five and 15 people were killed in a fertilizer plant explosion that also injured more than 160 others.
Waco police Sgt. William Patrick Swanton said early Thursday morning that the death toll is only an estimate as search and rescue operations remain under way in downtown West.
Swanton says there is no indication the blast was anything other than an industrial accident.
UPDATE: Thursday, April 18, 2:50 a.m.
The mayor of a Texas town where a fertilizer plant explosion injured more than 100 people says some firefighters who were battling a blaze when the blast happened aren't accounted for.
West Mayor Tommy Muska says there were five or six volunteer firefighters battling the blaze at the West Fertilizer plant when the explosion happened just before 8 p.m. Wednesday.
Muska, who is a volunteer firefighter himself, says not all of his fellow firefighters are accounted for. He says the blast knocked his helmet off and shattered the windows of his nearby home.
THe plant was cited for failing to obtain or to qualify for a permit in 2006.
The Texas Commission on Environmental Quality investigated West Fertilizer on June 20, 2006, after receiving a complaint June 9 of a strong ammonia smell. Agency records show that the person who lodged the complaint said the ammonia smell was "very bad last night" and lingered until after he or she went to bed.
Authorities say people were killed, but they don't know how many.
Authorities were still trying to evacuate area homes early Thursday morning.
A spokesman for the Texas Department of Public Safety says an unknown number of people were killed in a massive explosion at a fertilizer plant near Waco.
D.L. Wilson says it will be some time before authorities know the full extent of the loss of life and damage caused by Wednesday night's blast at the plant in West, about 20 miles north of Waco.
The explosion at West Fertilizer happened shortly before 8 p.m. and damaged buildings for blocks in every direction.
West is just north of Waco. The explosion could be heard as far away as Waxahachie, 45 miles away. A nearby resident said the blast was like being in a tornado because "stuff was flying everywhere." Debbi Marak says her windshield was blown out. She and her family fled after being told there could be another explosion.
Mayor Tommy Muska says the blast badly damaged buildings for a five-block radius around the plant, including a nearby middle school and nursing home. He says the nursing home's 133 residents were safely evacuated.
More than two hours after the blast, there were still fires smoldering in what was left of the plant and others burning in nearby buildings. In aerial footage from Dallas' NBC affiliate, KXAS-TV, dozens of emergency vehicles could be seen amassed at the scene. The explosion knocked out power to many area customers and could be heard and felt for miles around.
Authorities have set up a staging area on the local high school's football field, which was lit up with floodlights.
American Red Cross crews from across Texas were being sent to the site.