Ana Clara Benevides, 23, passed out during Swift’s second song in the Nov. 17 concert in Rio de Janeiro, “Cruel Summer,” and died hours later at a local hospital. Temperatures in the city that day were at about 40 degrees Celsius (105 Fahrenheit).

Fans lined up for hours before the show, and many accused organizers of failing to deliver enough water supplies for the more than 60,000 attending the concert at the Nilton Santos Stadium. They said they were not allowed to take their own water into the stadium.

The report by Rio’s Forensic Medical Institute said Benevides’ heat exposure led to a cardiorespiratory arrest. It also said she did not have preexisting conditions or substance abuse that could have led to her death.

The forensics expert who analyzed her body said in the document she had “serious compromise of her lungs and sudden death” due to the heat.

One of Benevides’ friends, who also attended the concert, told local media outlets in November they had been given water while waiting to enter the stadium.

Organizers T4F said in a statement the company “followed the best practices,” complied with “every demand from authorities” and “distributed thousands of bottles of water” to fans. TF4 also denied it did not allow people to bring their own water to the concert.

TF4 also said Benevides “was promptly cared for by members of a rescue team and sent (to the hospital) in an intensive-care unit ambulance.”

“In our 40 years in the business, this company had never registered a tragic episode” like Benevides’ death due to extreme heat, T4F said.

The office of Rio’s public prosecutor has opened a criminal investigation. Rio police said in a statement on Wednesday that after the forensics report is analyzed “representatives of the company organizing the event will be called to testify.”

Benevides’ death shook many in Brazil. She had taken her first flight to travel from the country’s center-west region to see her favorite singer.

In a statement posted on Instagram after the death, Swift said the case had left her with a “shattered heart.”

Benevides’s father, José Weiny Machado, told news website G1 he “never doubted the cause of death was the heat.”

His lawyer, João Paulo Sales Delmondes, said in a video shared with journalists that the forensics report “confirms the failings of the event’s organization.”

“Ana Clara’s family wants to wait until the investigations are finished to study what will unfold to punish those responsible in the criminal case and seek the necessary legal actions to claim for damages,” he said.