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Who was the voice in the rubble? That question has been one of the heartbreaking mysteries of the Surfside building collapse.

A review by Miami Dade Fire Rescue has concluded that it was Theresa Velasquez, a 36-year-old music industry executive from Los Angeles who was visiting her parents at the Champlain Towers South on the night of the collapse, according to a memo obtained by CBS Miami.

Her parents – Julio, 67, and Angela, 60 – also died.

Theresa Velasquez’s brother, David, said he accepts the findings of the fire department investigation. “There is no way to know 100%,” he told CBS Miami, “but it seems like the logical conclusion.”

According to the 11-page memo, written by Miami Dade Deputy Fire Chief Ray Jadallah, Velasquez did survive the initial collapse, but rescue crews were unable to reach her before she died.

Theresa Velasquez

CBS Miami

In the memo, dated April 25, and sent to Fire Chief Alan Cominsky, Jadallah notes his findings were based on more than two months of interviews with the crews who worked to extricate Velasquez.

The report attempts to refute the findings of a USA Today investigation published in December that identified the voice in the rubble as 14-year-old Valeria Barth. The report also rebuts allegations that the actions of the rescue crews caused Valeria to burn to death when firefighters accidentally set fire to the room where the teenager was trapped.

There were questions from the outset of the collapse about whether someone was heard alive in the rubble. Jadallah and others initially denied a voice was heard. Later the department acknowledged there was a voice in the initial hours behind a thick concrete slab that had crashed into the underground parking garage.

Those working in the underground garage all agreed the voice was female.

Some firefighters believed the voice said she was in Unit 204. That was the unit where Valeria was staying with her parents, Luis Fernando Barth and Catalina Gomez. They had travelled together to Miami from Colombia a month before the collapse.

Other firefighters said the voice said she was in Unit 304, which is owned by Theresa Velasquez’s parents.

The report notes: “…it was challenging hearing the woman.”

“One rescuer stated that when they asked the victim if she was with someone else, the female voice responded she was visiting her parents (paraphrased),” the report states. “This statement correlates with the accounts from Theresa Velasquez’s family stating that Ms. Velasquez was visiting her parents from California and was staying with them in apartment #304. Unlike Ms. Barth, who was accompanied by her parents visiting from Colombia and were occupying apartment #204.”

“According to rescuers, the voice was that of a grown woman whose English appeared to be that of an English speaker with native sentence syntax and excellent vocabulary,” the report continues. “All the rescuers unanimously stated … [the voice] did not have an accent.”

The report notes Valeria’s uncle said the teen’s primary language was Spanish “but she can speak English” and does have a distinct Spanish accent.

According to the report, Valeria’s uncle did not believe the voice was his niece.

CBS Miami was not able to reach either the uncle or Valeria’s grandmother.

Theresa Velasquez’s body was unearthed on July 8. It was approximately 15 feet from the support poles they had erected while they were attempting the extricate the trapped woman. However, the report does not say if Valeria’s body was also found in that area.

The report spends a great deal of time attempting to refute accusations the department did not have the necessary equipment to rescue the trapped woman. And it disputes the allegation that the firefighters accidentally sparked the underground fires that caused rescue efforts for the trapped woman to be halted for several hours. When they returned, they could no longer hear the woman’s voice.

The report documents the extremely hazardous conditions rescue crews were working under to try and save the woman — including high readings of carbon monoxide, hip-deep water polluted with hazardous materials and the constant risk of electrical shock and further collapse of the rubble.

Theresa Velasquez’s brother, David, said Jadallah and other officials have spoken to him often in the months since the collapse.

“I trust what is in that report and the people that made that determination,” he told CBS Miami.

Velasquez was a Los Angeles-based executive for the Live Nation event promotion company.

“Theresa was an impassioned leader at Live Nation, who elevated every project she was part of, at the same time breaking down barriers for women, and the LGBTQIA+ community,” the company said after her body was recovered. “We will always remember and honor the impact she made, and will miss her dearly.”