A woman and four children were killed in a late-night house fire in Franklin Township, Carbon County, the Carbon County Coroner's office said. 

The fire began at 12:21 a.m. Wednesday at a home on Willow Street.

The Carbon County Coroner's Office says the five victims are an adult woman, three male children and one female child.

The Lehigh County Coroner's Office & Forensics Center in Allentown completed the autopsies of all five people the following day, the Carbon County Coroner's Office announced on Thursday.

The victims have been identified as:

• 37-year-old Aida Marrero
• 14-year-old Kaylee Quevedo
• 6-year-old Matthias Wheelock
• 5-year-old Aiden Wheelock
• 1-year-old Nathaniel Wheelock

All deaths have been ruled as an accident. The cause of death for all victims ranges from smoke inhalation, thermal burns, inhalation of products of combustion and thermal injuries, the Carbon County Coroner's Office said.

"This is a profound and heartbreaking loss not only to the close-knit community of Franklin Township, but to the entire county. We recognize that family members are mourning and working to process this unimaginable tragedy," the Carbon County Coroner's Office said in a statement. "Please know that the community stands with you during this difficult time."

Three of the children killed in the fire were students in the Lehighton Area School District, the superintendent of schools said on the district website.

"While details are not publicly available as of yet, we have reason to believe that three Lehighton students, a Kindergartner, First Grader, and a Ninth Grader perished in this tragic event," Superintendent Jason Moser said.

"Please keep the families, friends, classmates, and anyone who has a close relationship with the deceased in your thoughts and prayers," Moser continued. "We will have dedicated spaces in each of our buildings available for any child who need to speak with qualified professionals to provide emotional support."

The Carbon County Coroner's Office and Pennsylvania State Police are investigating the cause of the fire.