EMBED >More News Videos Raw video shows a large fireball appear in the skies above the ITC facility in Deer Park.

EMBED >More News Videos Deer Park Fire: Time-lapse video offers look of smoke from fire burning for 3rd day

EMBED >More News Videos Parents concerned after classes resume while ITC fire still burns

EMBED >More News Videos Deer Park plant fire: What's burning and which schools are affected?

EMBED >More News Videos "This isn't an event we wanted or planned," ITC spokeswoman Alice Richardson said during a press conference Tuesday.

EMBED >More News Videos We could see and feel the impact of the Deer Park plant fire for days and possibly weeks, experts say.

DEER PARK, Texas (KTRK) -- A large flash of fire rose from the ITC facility in Deer Park Tuesday night as four tanks remained ablaze after erupting on Sunday morning.New video shows a large fireball suddenly appear in the skies over the facility, where officials from the state of Texas and ITC were steadfast in the information they've provided about the massive chemical fire.The cause of the fireball was not immediately known.On Tuesday, various officials stood firm on the public safety aspect of the large plume of black smoke hovering over southeast Texas. Despite the various chemicals being burned, both state and ITC officials said there was nothing toxic in the smoke in spite of reports of small debris falling.The fire has been burning since Sunday around 10:30 a.m. It started with one tank at Intercontinental Terminals Company. Emergency responders have been working with foam and water to try and control further spreading.Six tanks were on fire as of Monday, but ITC officials said flames spread to two empty tanks due to a temporary reduction of water pressure."The water pressure has been restored and responders have been able to fully resume their efforts to fight the fire," officials said.Meanwhile, classes resumed at La Porte and Deer Park ISD after the districts canceled classes Monday. But there was mixed reaction from parents, especially since you can still see the plume of black smoke above one of the schools in Deer Park ISD."Kids at San Jacinto Elementary will be able to see the fire out of their school window. You're putting our kids at risk for what reason? My kids will not be in school until the fire is out," a parent wrote.Another parent wrote on social media, "My kid will not be in class until the fire is out. My son's school is a couple of miles away. I will not gamble with his life."During a press conference Tuesday morning, ITC apologized to the community for the incident."This isn't an event we wanted or planned. Many of my employees work in the city of Deer Park, they live in Deer Park, they're out there fighting this fire the best they can," ITC spokeswoman Alice Richardson explained."They are residents. I would guess that probably 30 percent live in Deer Park in La Porte. They're concerned. Their families are concerned, so of course ITC would apologize to any of them," Richardson continued.The company claims testing done by independent contractor CTEH are below levels that would represent a public health concern.Despite the air quality monitoring, not everyone is confident we're in the clear."By looking behind me, you can tell this is not normal, this is not fine," said Corey Williams, policy and research director for Air Alliance Houston, on Monday. "The only thing preventing this from being a major catastrophe is favorable weather conditions."ITC officials say the first tank that caught fire contains NAPHTHA. The fire then spread to a second tank containing XYLENE. Both are gasoline components.Officials said the components are in gas blend stocks used in the production of finished gasoline and base oil used for machine lubrication.NAPHTHA can cause irritation to eyes and the respiratory system. It affects the central nervous system and is harmful and even fatal if it is swallowed.XYLENE may also be fatal if it is swallowed and enters the airway. It can cause skin irritation.Another tank that caught fire early Monday morning contains Toluene, which is used in nail polish remover, glue and paint thinner, plant officials told Eyewitness News.According to the Occupational Safety and Health Administration, Toluene is used in many products and workplaces like printing operations, manufacturing facilities, construction sites and nail salons.The Deer Park Office of Emergency Management released a message on social media about a hotline people can call because of an increase of claims following the incident at ITC.Officials initially said on Monday that it could take two days before crews are able to extinguish the flames. But since the fire intensified overnight, officials said Tuesday that they're unable to give a timeline on how long it will take for the fuel to burn off.