A 12-year-old boy has succumbed to his injuries a week after a shark in Sydney Harbour attacked him.

On Sunday, Jan. 18, Nico Antic was rushed to the Children’s Hospital at Randwick in a critical condition after being “bitten by a shark” along Hermitage Foreshore Walk in Vaucluse, the New South Wales (NSW) Police said in a news release.

Antic, 12, died in the hospital on Saturday, Jan. 24, just days after his parents, Lorena and Juan, had confirmed that he was brain dead, according to U.K. newspaper Metro.

“We are heartbroken that our son, Nico, has passed away,” his family wrote on GoFundMe. “Nico was a happy, friendly, and sporty young boy with the most kind and generous spirit. He was always full of life and that is how we will remember him.”

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“We would like to sincerely thank the first responders and the teams at Sydney Children’s hospital, Randwick, for everything they did to care for Nico,” they continued, also thanking their community for their support.

Antic had been jumping off a 6 m (19.6-foot) rock with two friends when the shark attack occurred. He was pulled out of the water by one of his friends, 7News Australia reported.

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“He kept fighting and breathing in my arms and he never gave up for a second…I’m grateful I was there for his last moments awake,” the friend told the outlet. “There was a brief second where Nico woke up while he was bleeding and he just looked at me and then stopped and I thought I lost him… I’m so surprised he fought for so long.”

Emergency services responded to reports of a boy bitten by what is believed to have been a bull shark in the area at 4:20 p.m. local time on Jan. 18, PEOPLE previously reported. He “suffered leg injuries” in the incident, according to the NSW Police.

Antic’s death comes just weeks before his 13th birthday, Metro reported.

The GoFundMe set up in his memory has raised over $250,000 towards its goal of $300,000.

The fatal attack is one of four shark incidents to have occurred in Sydney, Australia, in recent days.

On Jan. 20, a 39-year-old man suffered a chest wound after a shark “took hold” of his surfboard and bit him while surfing in New South Wales. A few hours before, a surfer in his 20s was critically injured in a shark attack at North Steyne Beach in New South Wales.