The shocking incident occurred at the Leste-Oeste beach in the city of Fortaleza in northern Brazil yesterday.
Luzimara Souza, a celebrated surfer in the region, and another person were in the water when a lightning bolt struck nearby.
Luzimara, 23, tragically died shortly after being rushed to the nearby Doctor Jose Frota Institute Hospital.
The second person, reportedly a 17-year-old, was caught on camera being rescued by onlookers.
In the harrowing footage, a bystander can be seen sprinting into the sea and helping bring the teenage boy onto the shore by lifting him off his surfboard.
Two men begin carrying his body to the shore.
Another clip – taken in a building on the beach – shows fellow surfers running in terror after the incident happened.
Gerardo Junior, one of the men who helped in the rescue effort, told reporters: “It’s unfortunate this fatality occurred.
“I arrived in the moment that our professional athlete was hit by lightning.”
Luzimara’s mother, Mara, said: “She usually surfed there, so she went there to surf and it started raining.
“Everyone was in the sea, there were six people.
“The man who went to rescue my daughter is here in the hospital.”
Luzimara began surfing at 10 years old and her trainer Jeova Rodrigues said she was training for the 2019 Brazilian Surf Championship.
She had also won the Ceara Championship in 2018 and was runner-up at one of the stages of the national tournament this year.
There are no updates on the boy’s condition.