The Lehigh County coroner on Friday formally identified four of the five people killed in a fiery explosion in Allentown on Wednesday.
DNA testing must be done to confirm the identity of the fifth victim, who was identified Thursday by family members as Beatrice Hall.
An autopsy determined both she and her husband, William Hall, 79, of 544 North 13th Street, died of multiple blunt force trauma as a result of the explosion.
Three members of one family, representing different generations, were also killed inside 542 North 13th Street. The family recently moved to the area from the Dominican Republic.
Katherine Cruz, 16, was a sophomore in the Allentown School District's Communities for Schools program.
"She had friends for awhile in the Allentown system, people who cared very much about her teachers and others," said Dr. Gerald Zahorchak, superintendent of the Allentown School District. "10:45 at night was home with her child and her grandmother."
The coroner said Katherine Cruz died of positional asphyxiation.
Her four-month-old son, Matthew Vega, died of carbon monoxide poisoning.
The cause of death for Catherine's grandmother, Ofelia Ben, 69, is still pending.
"It's okay to be upset about that," said Zahorchak. "It's okay to question. Its important to find people to talk to."
Zahorchak said the school district is mourning the loss of the bright student.
"We also continuously remind our staff that something like this for kids who are curious about it should be talked about," said Zahorchak, who added that talking helps in the healing process for older students. He urged both students and staff alike to remember Katherine Cruz and to reach out for counseling.
The coroner is withholding the manner of the victims' deaths until the investigation by his office and the Allentown Police and Fire departments is completed.