CROSBY, Texas — The investigation into Tuesday’s deadly explosion at the KMCO chemical plant in Crosby continued Wednesday morning.

James "Bubba" Mangum, 27, was killed and two more were sent to the hospital after an explosion around 10:45 a.m. rocked the area when a transfer line ignited a tank full of a chemical called isobutylene. The Harris County Fire Marshal's Office said the fire was contained by 4:20 p.m.

On Wednesday morning, there are 26 different agencies on site trying to figure out what went wrong.

The fire marshal's office has interviewed 50 people about the incident. They are in the site now, but not yet able to enter the fire zone.

Robert Soard, First Assistant County Attorney for the Harris County Attorney’s Office, said his office plans to sue KMCO over Tuesday’s fire once Commissioners Court approves the action. Soard says they’ll request authority during commissioners’ next meeting on April 9.

Officials are still keeping the public pushed back from the plant. There are roadblocks set up around the area just in case there happens to be another flare up.

The two people who were badly injured in Tuesday’s explosion are in critical condition Wednesday morning.

At least three chemicals burned in this fire. Tuesday evening, Texas Attorney General Ken Paxton filed a petition against KMCO for violations of the Texas Clean Air Act.

The subpoena will preserve documents related to KMCO and aid investigators in figuring out the cause of the fire.

Another lawsuit Harris County filed in August 2017 against KMCO alleging environmental violations is still pending.

On March 26, Harris County Attorney Vince Ryan also sued Intercontinental Terminals Company after the fire at their Deer Park chemical storage facility. Earlier that day, County Commissioners had unanimously authorized the action.

Harris County Commissioner Adrian Garcia was in Washington, D.C. Wednesday speaking with the EPA about the Deer Park blaze.

“Who would have thought that we would have event number three with KMCO while I was up here?” he said.

Commissioner Garcia’s Precinct 2 includes the sites of the three recent fires and dozens of similar petrochemical sites. The commissioner said he understands their importance to the local economy, but he’s also pushing the EPA to help Harris County improve air monitoring and crack down on rule-breakers that hurt both workers and neighbors. 

Commissioner Garcia said he’s also worried three bills under consideration at the Legislature – House Bill 2926, Senate Bill 17, and Senate Bill 26 – could weaken the county’s ability to hold these companies accountable.

“I would ask people to call their legislators, make sure that TCEQ and EPA are two watchdogs and not toothless puppies,” he said.

Dr. Bakeyah Nelson, Executive Director of Air Alliance Houston, agreed.

“I don’t know how many more of these incidents really have to take place before we start to take it seriously in this state in holding these facilities accountable,” she said.

Dr. Nelson said state lawmakers cut the TCEQ’s budget by $6 million during their last session. She also believes too many polluters get away with little to no punishment.

“The analysis that was done by Environment Texas showed that pretty clearly that during the past five years that only three percent of the violations that they found were actually given a fine,” Dr. Nelson said. “At that point, the fines aren’t even large enough where it would deter this kind of behavior.”

Dr. Nelson said there are 56 facilities in Harris County with significant violations of the Clean Air Act and the Clean Water Act.

However, Dr. Elena Craft with the Environmental Defense Fund believes lasting change won’t happen until the core issues – how often facilities are inspected and meaningful enforcement penalties – are addressed. 

Dr. Craft, who specializes in air toxics issues, wants more frequent state inspections, tougher penalties, and risk management plan review by the EPA.

She then added, “I always want to be hopeful, but the more incidents that happen, the less optimistic I am.”

RELATED: Chemical called isobutylene caused explosion, fire at Crosby chemical plant

On Tuesday, employees and residents in the area were pretty shaken up by the incident.

"It was terrifying. It was definitely terrifying... I don't know...there's always a danger but you never expect it to happen." an employee named Justin told KHOU 11.

He said employees made a mad dash for the exits.

RELATED: 'A mad dash to the exits': Employee describes Crosby plant explosion

Residents around the area reported a similar experience.

“The whole house shook,” said Dana Bushnell. “My windows vibrated, my dog was barking, the alarm was going off.”

“All at once I heard a big noise and my house shook!” said Roosevelt Stanley.

READ: Crosby plant explosion could be heard, felt from miles away

Employees inside the KMCO plant describe the moment as terrifying.

“Next thing you know there’s a huge explosion and you just saw people running out of the gate,” said KMCO employee Ben Villarreal.

Authorities say the fire started in a transfer line then quickly spread to a nearby tank and warehouse burning at least three chemicals: isobutylene, Ethanol and Ethyl acrylate.

RELATED: KMCO was criminally convicted of violating Clean Air Act in 2016

KHOU 11 viewers in Houston, Kingwood and Deer Park said they felt the explosion.

A large cloud of black smoke could be seen for miles throughout the day.

Harris County Sheriff Ed Gonzalez he heard a few "pops" coming from the plant after arriving on the scene.

Dozens of firefighters from Houston, Crosby and other communities battled the blaze for six hours.

Students at school districts in the area were forced to shelter-in-place while firefighters battled the blaze.

“It was shocking because it just happened,” said Bushnell, a mother of four picking up her kids from school. “I’m like, what is going on with these chemical plants?!”

“It is disturbing,” admitted Harris County Judge Lina Hidalgo during a press conference, “and it is problematic that we are seeing this incident at a facility especially on the heels of ITC.”

KMCO’s president, John Foley, offered an apology to the community.

“An apology for creating the situation...the worry, the angst. We take our commitment to the community and employees very seriously. It’s a great tragedy what happened here today," he said.

KMCO was criminally convicted of violating the Clean Air Act in 2016, KHOU 11 Investigates found, and was ordered to pay part of $3.3 million in criminal fines. The company has also been fined 10 times by the Texas Commission of Environmental Quality (TCEQ) since 1995.

The company sent out the following statement:

"There was an incident resulting in an ignition and fire today April 4, 2019 at KMCO, LLC in Crosby Texas. We are deeply saddened to confirm at this time that there have been injuries and one fatality. Those injured have been transported for medical treatment. Our hearts and prayers go out to the individuals involved, as well as our first responders, employees, and our community.

"We have activated the company’s emergency response team and incident command center. We are working with local first responders to extinguish the fire. We will give another update as additional information becomes available.

"We apologize for any inconvenience to residents in the vicinity. The wellbeing of our people, neighbors and the environment remain our top priorities."

The Environmental Protection Agency is monitoring air quality. The Texas Commission on Environmental Quality also sent emergency response personnel, along with an air quality van, to the vicinity.

“I offer my condolences to the families who have suffered injury or loss and to the community impacted by the KMCO fire earlier today,” says TCEQ Executive Director Toby Baker. “I applaud the attorney general for acting swiftly on my requests to hold KMCO fully responsible.”

This was the second major chemical plant fire in the Houston area in the last two weeks. The ITC fire that started on March 17 in Deer Park burned off and on for a week.

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RELATED: 'It was terrifying' | Deadly chemical plant fire in Crosby is contained

RELATED: KMCO was criminally convicted of violating Clean Air Act in 2016

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