At least two people were killed in an explosion at a plant in Houston early Friday, authorities said.
Reports of the explosion started coming in to Houston police around 4:15 a.m., with reports on Twitter of a boom felt across the city. The blast scattered rubble as far as a half mile and damaged nearby homes.
Download the NBC News app for breaking news
“This is in essence a disaster area,” Houston Police Chief Art Acevedo said of the neighborhoods around the manufacturing facility.
Let our news meet your inbox. The news and stories that matters, delivered weekday mornings.
The explosion occurred in a building at Watson Grinding and Manufacturing, which makes valves and provides thermal-spray coatings for equipment in various industries, according to The Biorports.
Acevedo said earlier Friday that one worker at the plant was unaccounted for but that a search could not take place until crews had closed valves that were releasing chemical polypropylene, NBC affiliate KPRC in Houston reported.
Polypropylene is a chemical compound that is lighter than air and will dissipate, according to the outlet.
Police have not released the identities of the two people killed, and it was not immediately clear if one of them was the missing worker.
At least one person was taken to a hospital, the city’s fire department said.
A lot of homes adjacent to the explosion site suffered “significant damage,” with some of them knocked off their foundations, city fire chief Samuel Peña said. A nearby strip mall also had extensive damage, he said.
Residents in a nearby neighborhood in the northwestern part of the city told NBC affiliate KPRC in Houston that the blast blew out windows and damaged garage doors.
“It knocked us all out of our bed, it was so strong,” Mark Brady, who lives in the neighborhood, said. “It busted out every window in our house. It busted everybody’s garage door in around here. … It’s a war zone over here.”
The Houston Fire Department opened a criminal investigation into the explosion, as part of its protocol. The U.S Department of Alcohol, Tobacco, Firearms and Explosives in Houston said in a tweet that it is assisting police in the investigation.
“We have no reason to believe, we have no evidence that terrorism is involved, that a criminal act is involved,” authorities said. “When you have this type of incident, part of our protocol is to conduct a criminal investigation.”