Members of two families suffered second- and third-degree burns and fractures in a Syracuse house explosion that happened Tuesday afternoon, according to a Upstate University Hospital spokesperson. As of Wednesday afternoon, no cause was known for the explosion. 

The hospital said they treated 11 patients, and some remain in intensive care as of noon on Wednesday.

Syracuse Mayor Ben Walsh said a family of seven lived inside the home at 205 Carbon Street, and six others who were at the home when it exploded at 4 p.m. were visiting. The victims were a mix of adults and children. All 13 people have been accounted for, officials said. National Grid testing confirmed no issues with their equipment on the site.

(Spectrum News 1)

One of the families, a family of seven, included a 42-year-old male; a 33-year-old female; and five children, ages 13, 10, 12, 8 and 3. The 3-year-old is in critical condition, and all others are stable, Craner said Wednesday morning.

The other family, a family of six, included a 34-year-old male, a 29-year-old female, and four children, ages 5, 4, 2 and 9 months. The 4-year-old was not admitted to the hospital for further treatment; the 2-year-old and the 9-month-old are listed in critical condition, and the others are stable.

Doctors who treated the victims said second-to-third-degree burns and fractures were among the injuries treated.

One child was in a parked car when the house collapsed, but was rescued and treated. Some in stable condition have been able to see their family members, while others are still fighting for their lives.

“Seeing that many kids come in and just knowing the family situation – that they were all worried about their family members – it does provide some stress to you personally. But that's why we have everything so standardized, and why we have a team approach that we use every time,” said Kim Wallenstein, pediatric trauma medical director at Upstate Golisano Children’s Hospital.

Walsh said the city was unaware of any code violations at the home.

Firefighters and rescue units, working in tremendous heat, sifted through the structure Tuesday evening to see if anyone may be trapped inside as part of a slow and methodical rescue operation throughout the evening, city Fire Department Chief Michael Monds said.

Due to the temperature, first-responders were being rotated as a safety precaution, he said.

In a statement, Gov. Kathy Hochul said she had spoken to Walsh about what she called a "gas explosion." She New York state is offering assistance and support to emergency response teams.

Firefighters continued their investigation throughout the night. Search and rescue dogs were brought in to help.

“Our investigation has shifted specifically to focus on the house," Syracuse Fire Department District Chief Matt Craner said. "And again, that investigation is ongoing. We’ve had our investigators in there. We've had police investigators in there. And again, we're just working to rule out all of those potential causes."

Concerned neighbors on Carbon Street who were in their homes when the explosion happened described a loud bang. Some people who were in the house have been interviewed as part of the investigation as officials work together to find a cause.

“It is like finding a needle in a haystack, searching through that pile of rubble," Craner said. "But again, it speaks to the quality of the firefighters that we have with our department, the quality of the members of the other agencies that have responded that, you know, we are able to kind of sort through this and, you know, hopefully be able to come up with a concrete cause for this that we'll be able to share.”

National Grid workers were also at the scene. 

They ran a test on the natural gas supply from the curb to the meter in the house, which came back clean, Craner said.