(CNN) — Hours after a series of explosions rocked a Texas chemical plant outside Houston early Wednesday, officials said there is no way to know how long the fire will burn.
Around 1 a.m. (2 a.m. ET), an explosion at the TPC Group plant caused extensive damage across the small city of Port Neches, leaving at least three employees injured, authorities said. During a press conference, they said a series of smaller explosions occurred throughout the day and then a larger one in the afternoon launched a tower into the air with balls of fire.
A mandatory evacuation has been issued for areas within a 4-mile radius of plant because of the potential for more explosions.
Jefferson County Judge Jeff Branick, who issued the mandatory evacuation, said the initial explosion knocked out power to the plant. Authorities have no “ability to check the volume of available chemicals” and “no way to calculate burn rates” going forward, he said.
Officials have focused on containing the blaze and keeping surrounding storage tanks cool, according to Troy Monk, director of health safety and security for TPC Group, which operates the Port Neches manufacturing plant about 90 miles east of Houston. The next priorities will be putting out the fire, then investigating its cause, he said in a press briefing.
“Right now, it’s contained and not going anywhere but it’s not under control,” Jefferson County Sheriff’s Office Capt. Crystal Holmes told CNN.
Personnel were evacuated from the plant, which makes products for chemical and petroleum companies, said TPC Group. About 30 people — out of 175 full-time employees and 50 contractors — were on site at the time of the explosion, Monk said. He added that two injured employees and a contractor were treated and released from medical facilities.
The fire is burning a chemical called butadiene, police said. The colorless gas is considered a health hazard, according to the US National Library of Medicine. It is made from processing petroleum and is used to make synthetic rubber and plastics.
The Texas Commission on Environmental Quality said the 1,3-Butadiene levels at a monitoring station about 4 miles west of the incident, “are well below concentrations of health concern or odorous levels.”
‘Extensive damage’ in Port Neches
Branick, the judge, told CNN that officials became concerned after the second explosion launched the tower into the air “like a missile” in the direction of Port Neches-Groves High School.
There were no students at the school at the time but officials were worried other columns from the plant might be heaved into a nearby storage tank facility, causing more explosions, he said.
Besides Port Neches, mandatory orders include the cities of Groves, Nederland and the northern part of Port Arthur.
From an office in nearby Nederland, Kelly Berka saw the plumes of smoke from after the afternoon explosion.
“What a damned mess,” Berka wrote on Twitter. “We’re clearing out.”
Berka told CNN her co-worker, who lives near the plant, had her front door blown off earlier in the morning before evacuating.
Holmes confirmed the morning blast sucked doors out of homes.
Port Neches police said that blast caused “extensive damage” throughout the city.
“Please stay off the roads anywhere near the refineries. Obey all the barricades that are in place,” police said in a statement.
‘I noticed an orange glow’
Some Port Neches residents said their windows were blown out by the blast. Monk said he awoke to his front and back doors being blown into their frames.
“I understand what getting blown out of bed means now,” Port Neches Mayor Glenn Johnson told reporters.
Tyler Shawn Dunlap was sleeping when the explosion rocked his house.
“I heard and felt my house shake. I first thought people were coming to break in ’cause of our intense security,” he told CNN. “I went to dad’s room, and he thought our generator blew up so we checked that, then I noticed an orange glow from the clouds.”
Trent Lee said the explosion sounded like a nuclear detonation. It shook everything in Port Neches.
The blast was captured on Mia Hubert’s doorbell camera and left the area covered in a fiery hue.