Update, Wednesday 10:30: According to the company’s spokesman, two workers died at the factory on Payne Street.

The other 10 people injured in the explosion that occurred on Tuesday afternoon are still receiving treatment. It’s not yet clear what caused the explosion, and Louisville officials say it will take some time for any investigation to be completed.

University of Louisville Hospital Chief Medical Officer Dr. Jason Smith provided an update on the condition of the injured victims Tuesday night. Smith said two were in critical condition while the other five were stable.

“The biggest problem with blast injuries is that it’s actually a little bit of everything, burns, blunt injuries, penetrating injuries, debris, chemical explosions, and can get stuck from chemical exposure,” Smith said. “So from that perspective, it’s great to have a team like this that can handle explosions.”

Smith said victims arriving at UofL Hospital had to go through a decontamination process that lasted up to 15 minutes.

City officials continue to say no hazardous chemicals are leaking into the air.

Those who have debris from the explosion falling on their property are advised not to touch the objects and to call 311 immediately.

Original story: An explosion at Givaudan Sense Color in Louisville around 3 p.m. Tuesday sent dozens of workers fleeing the factory. The factory at 1901 Payne Street produces colorants for sodas and foods. Medical teams arrived at the scene and took 11 workers to the hospital. One person trapped in the building was rescued.

The cause of the explosion was still unknown Tuesday afternoon, but it caused major structural damage to the factory and blew out windows at some nearby homes and businesses. Two people who live at Axis in Lexington Apartments, about a third of a mile away, said they felt the building shake.

At a news conference near the facility, Mayor Craig Greenberg said weather observations showed no indication that the explosion released toxic chemicals into the air.

“We’re trying to get more details from the company so we can know more about what happened inside the facility and what chemicals may have been involved,” Greenberg said. “We do not have that information at this time.”

Immediately after the explosion, city officials warned everyone within a two-mile radius to shelter in place. As of 4:30 p.m., the shelter-in-place order had been lifted, but residents living within two blocks of the Givaudan plant were still asked not to return to their homes.

A man on a sales trip from Cincinnati who asked not to be named said he was inside the factory when the explosion occurred. The man said he left the building after hearing a loud explosion. He said he saw at least one person leave the facility on a stretcher covered with something that appeared to be molasses or a coloring agent.

Another man said he was parking his truck just outside the factory gate when the explosion occurred. He said material from the factory flew onto his truck and left a large hole in his windshield. He also did not want his identity to be disclosed.

This is the second explosion to occur at the facility. In 2003, a vessel inside the factory exploded, causing what authorities said was a “massive release of aquatic ammonia.” One person died in that incident.

A 2004 analysis by the U.S. Chemical Safety and Hazard Investigation Board found that lack of training and safety procedures were the primary causes of the plant explosion, then owned by DD Williamson & Co., Inc.

This second explosion will be investigated “for some time,” and it will take some time before any cause is determined, Louisville Fire Chief Brian O’Neill said Wednesday.

Residents are asked to avoid the area surrounding the 1900 block of Payne Street while emergency services continue their work.

This story has been updated with new information about casualties, injuries and debris from the explosion.