The death of a young Brazilian fan who fell ill at a concert by U.S. singer Taylor Swift in sweltering Rio de Janeiro last month was due to heat exhaustion, police said on Wednesday.

On November 17, Ana Clara Benevides, 23, passed out at the Nilton Santos Stadium while watching the first of Swift’s six gigs in Brazil as part of The Eras Tour. After being escorted to the on-site medical station, Benevides was subsequently moved to the Salgado Filho Hospital, where she passed away.

According to a police report released on Wednesday, Benevides died from heat exhaustion, which resulted in respiratory and cardiovascular problems. The official cause of death was listed as “alveolar hemorrhage and polyvisceral congestion caused by diffuse exposure to heat.”

Rio police opened a probe into the firm last month.

“Company representatives will be called to provide clarifications following this report,” police said in a statement on Wednesday, adding that the investigation was ongoing.

Following the news of Benevides’ death, Swift wrote on Instagram that she had a “shattered heart” and was “devastated.”

She postponed her second Rio concert the next day due to scorching heat, but went ahead with the remaining shows on the Brazilian leg of The Eras Tour.